This article focuses on another important network model, the Cisco hierarchical network design model. Very different that the OSI model, this model is used as the basis for designing Cisco networks for security and performance. The article provides an overview of the roles and responsibilities of each of the model’s 3 layers.
While the OSI model is concerned with how different systems communicate over networks, the Cisco hierarchical model is a blueprint of types that defines how networks should be designed in layers. Each layer is meant to have its own roles and responsibilities, but the goal is to create a network that delivers high performance, is manageable, and keeps required roles in their place. While this model was designed by Cisco, its use can by all means be adapted to account for the switching and routing equipment of any vendor.
The model is made up of three layers, including Core, Distribution, and Access. The diagram below shows each of these layers relative to one another.
The Core layer of the network would be considered along the same lines as the backbone – high speed and redundant. The Distribution layer would contain intermediate switches and routers, such as those used to route between subnets or VLANs. The Access layer is literally where user’s PCs plug into their local switch, somewhere like an area wiring closet. While this is a simplified view of the network, it provides a general high-level overview.
Getting a little deeper into things, each layer of the model is actually home to multiple roles and responsibilities. Remember that this is a model, and as such not all networks will necessarily look like this – many, especially smaller ones, may not even be close. Instead, think of this model as one that outlines best practices to ensure that the network is reliable, scalable, and meets performance requirements.
Each layer in the model has a general level of responsibility, in terms of what capabilities should be implemented there, and with a particular emphasis on how that layer should perform. Each of the layers is outlined in more detail below.
The responsibility of the core layer is to act as a high-speed switched backbone. Notice that the backbone is expected to switch traffic, and not route it. Routing can severely impact performance, mainly because each frame needs to be recreated as it passes through each router, as we’ll look at a little later in the series. Switching provides much higher performance, mainly because a frame can travel across the backbone without needing to be recreated at each switch. That’s not to say that the frame isn’t inspected at every switch (it will be to varying degrees), but everything stays at OSI layers 1 and 2 instead of having to be considered at Layer 3. The Core layer is usually comprised of a relatively small number of high-end switches. Growth should not add devices, but rather replace devices with higher-speed equipment as necessary.
The Core Layer is also responsible for providing a degree of redundancy by providing multiple paths. That is, you want to be sure that even if a backbone link goes down, another path exists over which frames can travel. We’ll consider this in a diagram shortly.
In general, you want to be sure that the only traffic that moves across the backbone is that which is moving between different Distribution-layer devices. A design that moves traffic over the Core layer when it isn’t necessary will not provide the best performance. To that end, the core should also never be used to implement traffic filters such as access lists – these should be implement at other layers instead.
To summarize, the Core Layer should:
- Be used to provide high-speed switching.
- Provide reliability and fault tolerance.
- Grow by using faster, and not more, equipment.
- Never implement performance-decreasing elements such as access lists.
The distribution layer acts as an intermediary between the Core and Access layers, and is usually where the routing functions (and more) on a well-designed network are found. An example of the type of interconnection here includes those between different types of media such as Ethernet and Token Ring. The distribution layer is also where policies are usually implemented using Access Lists.
To get a feel for the function of the distribution layer, remember that a great deal of routing will usually happen on a network. Clients on one subnet may need to talk to servers on another. In some cases this traffic is localized, such as with departmental file or database servers. However, there are often servers that need to be accessed by many subnets even within a given location, such as mail servers. The distribution layer would be responsible for this routing function. In all, this layer serves a number of purposes including the implementation of
- Security, in the form of Access Lists and filtering.
- A boundary for route aggregation and summarization (for example, many subnets can be hidden behind a single routing table entry, making these entries smaller, and routing more efficient).
- Broadcast domains. A broadcast domain is a layer 2 concept that defines how far a broadcast will travel on a given network. By default, routers usually do not pass broadcasts, acting as the demarcation point between broadcast domains.
- Routing. Almost all routing is done at this layer, which keeps it away from the backbone. This also acts as the intermediate point between where static and dynamic routing are used on the network.
The Access Layer acts as the point as which end stations connect to the network, usually by plugging into Layer 2 switches or hubs. As such, this layer is usually used to define network collision domains. The Access layer is also sometimes used to define additional network security policies and filtering if necessary.
How it fits together
The diagram below shows how a typical network might be configured to account for the Cisco hierarchical network design model. Remember that the Core layer switches might be geographically dispersed, and that the distribution layer routers might be connected to the core via a WAN link of similar.
Rs from http://archive.networknewz.com/2004/0206.html
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As more and more 802.11ac devices come to the market this year, businesses need to make sure the best possible 802.11ac wireless infrastructure gets deployed to make sure those 802.11ac end points are performing at both the best possible data rates and application throughputs to maximize the move to 802.11ac.
Cisco’s Aironet 3700 with HDX Technology does just that. If you’re thinking that the 3700 is just another 802.11ac AP, think again: not all 802.11ac AP’s are created equal.
To demonstrate this, let’s take a Cisco 3700 access point...
When you open a Cisco AP, you will see dedicated memory (RAM) on the radio chipset itself (one on the 2.4 GHz radio, another on the 5 Ghz radio) to ensure the RF packets get processed “onboard” each radio instead of “offboard” in order to reduce latency and any packet processing collision from memory contention on the AP. Additional packet processing can be handled on the “offboard” memory that is part of the network processor portion of the AP platform as well. This unique, innovative ASIC-based Wi-Fi chipset by Cisco exemplifies the built-for-Purpose design, and is the hallmark of Cisco’s 3700 Series AP.
Contrast this with the competitive landscape that claims to be Purpose-Built, but in reality is leveraging off-the-shelf merchant silicon-based 802.11ac WiFi chipsets. You will see on these AP’s, the memory is only available “offboard”—introducing packet transfer latency and collision—due to a shared memory between the radios and network processor. It’s that difference that explains why with a Cisco 3700 AP, you can scale 40 or more clients without aggregate throughput drop.
Built-for-Purpose also means Cisco AP 3700 comes with HDX Technology’s ClientLink 3.0, which ensures that all 802.11ac devices are operating at the maximum 11ac data rates. I speak from personal experience--my 802.11ac enabled Macbook Air shows over 800 Mbps consistently. Without Cisco’s built-for-purpose feature set, an 11ac smartphone could be toiling around at 11n rates instead—now where’s the fun with that?
At the end of the day, a built-for-purpose AP from Cisco is going to go the distance and bring you and your end-users the highest performance, optimized for the latest devices. When building out your wireless infrastructure to support all the devices and services on your network, don’t forget: not all 802.11ac AP’s are created equal, so know what you’re getting into when selecting an access point.
More Cisco Access Point Comparison: Cisco AP 600 Series vs. 700W Series AP
Cisco Aironet 802.11n G2 Series Indoor Access Points
AP 600 Series
Cisco AP 700W Series
Hospitality, university residence halls
Application performance profile
In-room wired and wireless access device,
Number of radios
Dual (2.4GHz and 5.0GHz)
Dual (2.4GHz and 5.0GHz)
Max data rate
MIMO radio design: spatial streams
2 x 3:2
2 x 2:2
Client count/ClientLink client count
100 wireless and 4 wired;
Autonomous access point option
Rogue access point detection
Adaptive wireless intrusion protection system (wIPS)
100 to 240 VAC,
802.3at/af, AC adapter,
0 to 40°C
0 to 40°C
Limited lifetime warranty
Rs from: https://blogs.cisco.com/wireless/not-all-802-11ac-aps-are-created-equal-built-for-purpose-vs-purpose-built/
More Related Topics of Cisco Aironet 802.11n G2 Series Indoor Access Points
The Cisco Aironet 2700 Series is a dual-band, 802.11ac supported Wi-Fi Access Point optimized for adding capacity and coverage to dense Wi-Fi networks.
It also serves the performance needs of the latest BYOD clients now shipping with 802.11ac connections.
Delivering high performance for any small, medium-sized, and large enterprise network, the Aironet 2700 Series uses a purpose-built chipset with best-in-class RF architecture. It has been created specifically to take advantage of all the new speed and function of the latest Wi-Fi technology standard but at a price point that lets you ease into 802.11ac networking.
The Aironet 2700 Series Access Points is offered in two models:
- Cisco Aironet 2700i Access Point has a sleek design with internal antennas and is ideal for office environments.
- Cisco Aironet 2700e Access Point model is available for challenging indoor environments and requires external dual-band antennas.
The Cisco Aironet 2700 Series Access Point:
•Delivers the most advanced features in its class
•Includes an integrated 802.11ac radio that supports 3x4 MIMO with three spatial streams. The fourth receive antenna provides a performance advantage over all competing 802.11ac solutions on the market today.
•Supports true beamforming for clients that support one, two or three spatial streams
•Offers Cisco HDX support. HDX includes Cisco CleanAir within 80MHz channel widths, ClientLink 3.0, and RF Turbo Performance for better performance of all clients in a dense environment.
•Offers a 2700e model for harsh/challenging indoor environments. This model requires external dual-band antennas.
High Density Experience (HD Experience)
Building on the Cisco Aironet heritage of RF excellence, the 2700 Series APs run on a purpose-built, innovative chipset with a best-in-class RF architecture. This chipset provides a high-density experience for enterprise networks designed for mission-critical, high-performance applications. The 2700 is a component of a Cisco series of flagship, 802.11ac-enabled APs that delivers a robust mobility experience based on the following product features:
● 802.11ac with 3x4 multiple-input multiple-output (MIMO) technology supporting three spatial streams. This architecture offers a sustained 1.3-Gbps rates over a greater range for more capacity and reliability than competing APs.
● Cross-AP Noise Reduction, a Cisco innovation that enables APs to intelligently collaborate in real time about RF conditions so that users connect with optimized signal quality and performance.
● Optimized AP Roaming to ensure that client devices associate with the AP in their coverage range that offers the fastest data rate available.
● Cisco ClientLink 3.0 technology to improve downlink performance to all mobile devices, including one-, two-, and three-spatial-stream devices on 802.11ac. At the same time, the technology improves battery life on mobile devices.
● Cisco CleanAir technology enhanced with 80MHz channel support. CleanAir delivers proactive, high-speed spectrum intelligence across 20-, 40-, and 80-MHz-wide channels to combat performance problems due to wireless interference.
● MIMO equalization capabilities, which optimize uplink performance and reliability by reducing the impact of signal fade.
The Cisco Aironet 2700 Series sustains higher-speed connections farther from the AP than competing solutions. The result is up to three times greater availability of 1.3-Gbps rates in the Cisco environment for optimum mobile device performance and user experiences.
Cisco also offers the industry’s broadest selection of 802.11n and 802.11ac antennas, delivering optimal coverage to different deployment scenarios.
The Cisco Aironet 2700 Series is a component of the Cisco Unified Wireless Network, a foundation for operating both wired and wireless LANs in an integrated manner. The Unified Wireless Network can scale to as many as 18,000 APs with full Layer-3 mobility across locations on the enterprise campus, in branch offices, and at remote sites. The Cisco Unified Wireless Network delivers highly secure access to mobility services and applications. It offers the lowest total cost of ownership (TCO) and investment protection by integrating smoothly with existing wired networks.
The 802.11ac-enabled Cisco Aironet 2700 Series Access Point will help partners seize huge mobility opportunities while enabling more customers to accelerate their path to Gigabit Wi-Fi. This is the foundation for a fast, dependable and secure wireless Local Area Network (LAN) infrastructure that can support the many mobile devices, apps and data running in high-density customer environments.
Availability: The Cisco Aironet 2700 Access Point will be available in April 2014 and priced starting at $1,095 U.S.
The introduction of 802.11ac, the latest Wi-Fi standard, brings higher data rates, better performance, and better coverage compared to earlier standards. The 802.11ac standard uses a wider channel and an improved modulation scheme that also supports more clients. It is built on the success of the 802.11n standard, improving and enhancing the best practices and making it one of the most efficient standards to date. In addition, the presence of 802.11ac can provide more efficiency for 802.11n clients.
For some organizations, the technological efficiencies of 802.11ac is creating a race to upgrade their wireless networks. The race to upgrade is also being driven by the fact that the Wave 1 portion of 802.11ac, with a maximum data rate of 1.3 Gbps, could be the last Wi-Fi solution that organizations can expect before having to upgrade their switches. This combination of factors is causing 802.11ac adoption to increase at a rapid rate, resulting in better performance and coverage for wireless networks.
With increased performance and coverage comes increased traffic. There has also been an increase in the demand for client access, including 802.11ac-enabled clients, a trend that started before 802.11ac was approved as a standard. Many businesses and organizations in industries ranging from higher education and K-12 to healthcare, manufacturing, and retail are facing the same challenges: more users are coming onto the network, users are bringing more devices, more devices offer only wireless connectivity (no Ethernet port), security demands are greater, there are more operating systems to support, and lastly, application updates are needed on each of the devices. All this leads to the larger problem of high density.
However, not all 802.11ac access points are alike and some are not designed to handle higher density. To get the most out of an 802.11ac deployment, an organization must take into account certain fundamental considerations.
Enter Cisco High Density Experience (HDX) technology. Available on the Cisco Aironet 3700 and 2700 Series Access Points, Cisco HDX technology is a suite of solutions combining a feature set designed specifically to alleviate the introduction of more clients, more access points, bandwidth-hungry applications, and high-density network strain while providing an unparalleled user experience.
HDX helps optimize performance, mitigation, scalability, and roaming for high-density wireless networks. Additionally, HDX is a hardware-based solution on a Wi-Fi chipset designed by and for Cisco. It is not simply a set of software features based on a merchant silicon Wi-Fi chipset. It is a purpose-built application-specific integrated circuit (ASIC) that allows networks to get the most out of 802.11ac while also improving the overall performance of their wireless network.
HDX features include the following:
Cisco CleanAir for 80-MHz Channels
With Cisco CleanAir for 80-MHz channels, Cisco has fundamentally retooled the award-winning CleanAir technology to support the entire 80-MHz channel supported by 802.11ac while providing the same level of granularity and accuracy of RF interference detection as before.
The benefit of an 80-MHz channel is the potential to double usable throughput in comparison to the 40-MHz-wide channel used by 802.11n. However, a wider RF channel is also more susceptible to interference. In other words, 802.11ac devices “hear more” than 802.11n devices, primarily due to the wider channel support.
Not all 802.11ac access points perform well in the presence of interference. With the increasing number of clients per access point, number of access points in a given wireless network, and number of wireless networks themselves, wireless network operators and administrators are challenged to maintain performance when interference exists. In brief, for high-performance and high-density environments, spectrum intelligence continues to matter. When interference can be detected and identified, it can be mitigated.
For these reasons, Cisco CleanAir technology is a key feature in Cisco’s HDX solution. Because of the increased channel bandwidth for 802.11ac networks, and the increasing density of wireless networks, CleanAir is essential to help assure that no significant degradation or suboptimal performance results from the migration to 802.11ac and the concurrent growth in high-density deployments.
Cisco ClientLink 3.0, as part of HDX, can perform Cisco’s patented beamforming technology with 802.11ac clients as well as 802.11a/g/n clients. In fact, ClientLink 3.0 complements standards-based Explicit Compressed Beamforming Feedback (ECBF) in which more and more 802.11ac clients will actively participate. ClientLink 3.0 improves the downstream performance and throughput from the access point to the client as well as improving the upstream performance and throughput from the client to the access point. This improves the quality of the connectivity between client and access point, resulting in a more stable network connection.
ClientLink 3.0 will also benefit the wireless network transition from 802.11n to 802.11ac. Every new wireless standard adoption comes with the challenge of a mixed-device environment. We saw it when running 802.11n with the mix of 802.11a/g devices, and we are now seeing it with 802.11ac and a more convoluted mix of 802.11a/n devices. There is a high chance that your office or enterprise will have a blended presence of legacy 802.11a, 802.11n, and 802.11ac client devices coexisting together. ClientLink 3.0 helps solve issues involved in mixed-client networks by enabling higher data rates for both legacy and newer clients, even when they are connected to the same access point. With ClientLink 3.0, networks will be able to enjoy the benefits of 802.11ac with a more efficient and higher-performing Wi-Fi experience.
Turbo Performance with HDX technology allows the supporting access points to scale to 60 clients or more, with each client running media-rich video or interactive traffic, without any performance degradation. This is especially important in networks with high client density, in which some competitors fall short at 10 or 20 clients.
Turbo Performance is important with 802.11ac because of the higher data rates, which equate to more packets per second (PPS) flowing through the access point. For example, with 802.11n, an access point might have had to push 30,000 1500-byte packets per second (PPS) through the access point’s data plane. Today, with 802.11ac, that could be 75,000 PPS or more. More PPS means more load on the access point’s CPU, so to really keep up with the demands of 802.11ac, a redesigned access point is needed.
With Turbo Performance, Cisco has fundamentally retooled its access point design specifically for 802.11ac. The result is much less CPU-intensive processing and a much more efficient packet scheduler delivering 802.11ac speeds at a much larger scale than the competition. 802.11ac allows for speeds never before seen on a Wi-Fi access point. Cisco understood the demands caused by these increased speeds and, with HDX Turbo Performance, has fundamentally reworked the data plane in order to enable unrivaled 802.11ac performance and scalability.
Optimized Roaming allows clients to roam more intelligently and cleanly between access points as well as between unlicensed and licensed cells. It addresses a fundamental problem called stickiness in which the client stubbornly stays connected to an access point that it connected to earlier, even though the client has physically moved closer to another access point.
With Optimized Roaming, a Cisco access point continuously evaluates the quality of the Wi-Fi connection for each associated device and can actively disconnect a device upon detecting that the device is moving into a region of poor coverage. This disconnection forces the client to enter its scanning mode much earlier than it ordinarily would, terminating a connection that is becoming essentially unusable and allowing the client to connect to an access point with better performance.
Optimized Roaming not only benefits the end user but also improves the overall performance of the access points and therefore the experience of other users. A client that is gradually degrading in performance (and possibly degrading faster than it can dynamically rate-adapt to or compensate for) may cause a large number of retransmissions, which consume airtime. If enough clients are being sticky, the performance of the access point can be degraded. Therefore, sticky clients that maintain poor connections can easily affect well-behaved clients.
Optimized Roaming helps prevent a negative experience for Wi-Fi users by monitoring the connection quality of all devices and proactively prompting poorly performing client devices to seek a better connection much sooner.
RF Noise Reduction
RF Noise Reduction allows the access point to be more efficient in its use of the RF spectrum and possibly to recycle channels. This feature allows neighboring or adjacent access points to use the same channel to increase overlay density and mitigate configuration errors. With RF Noise Reduction, it is possible to deploy more access points in a given area to meet strenuous service-level agreements (SLAs). This is important for networks with extremely high client density, because it allows the deployment of additional access points to handle the higher client demand. RF Noise Reduction will be available in a future release.
If you are an enterprise IT manager and you are considering deploying 802.11ac for your wireless network, you must ask yourself if all 802.11ac access points are alike. 802.11ac has some great benefits, such as wirelike speed and the ability to handle a high concentration of clients. However, there is more to consider when deploying 802.11ac. For instance, how do you handle RF interference now that 802.11ac supports 80-MHz channels? Will legacy devices such as 802.11a/g/n allow you to achieve the best performance that 802.11ac is capable of? How can you ensure that your users get the best wireless performance when they roam across a building? And lastly, as more clients join the network, is your performance going to suffer? These are all valid concerns that Cisco addresses with its HDX solution. HDX is a necessary component of a wireless network, complementing 802.11ac while helping ensure that you get the best performance out of your wireless network.
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In this article we will introduce the new Cisco 4451-X Integrated Services Router, which builds on the concept of the truly Application Experience router by integrating multiple services into a single platform that can provide all the services a typical branch office needs. The services include increased capacities for routing, switching, unified collaboration, security, WAN acceleration, application optimization and Application Visibility and Control (AVC). At the same time, the new routers are designed for expansion that can deliver increased performance and capabilities over time without the need for expensive system upgrades or hardware as remote sites grow.
So what are the main features of Cisco 4451-X isr, benefits, capabilities, specs, software, modules, etc.? We will list more questions about Cisco 4451-X series, you can check the main points that you want to get…
Q and A: Cisco 4451-X Integrated Services Router
Q. What are the key new features and changes that are being introduced in the Cisco 4451-X?
A. The Cisco 4451-X offers:
● Default forwarding bandwidth of 1 Gbps upgradable to 2 Gbps with a software-activated upgrade license
● The ability to house three network interface modules (NIMs) and two enhanced service modules (SM-Xs)
Q. Where do I position the Cisco 4451-X in comparison to the Cisco 3900 Series and Cisco ASR 1000 Series Aggregation Services Routers?
A. The Cisco 4451-X is positioned for high-end enterprise branch offices or enterprise headend where there is a performance requirement of 1 to 2 Gbps with services. Performancewise the Cisco 4451-X is positioned between the Cisco 3945E ISR and the Cisco ASR 1001.
Q. What software is the Cisco 4451-X capable of running?
A. The Cisco 4451-X Series runs the Cisco IOS ® XE Software. The initial version of software release will be the Cisco IOS XE Software Release 3.9.1 for the Cisco 4451-X.
Q. Does the Cisco 4451-X run a similar software release as the Cisco ASR 1000?
A. Yes. The Cisco 4451-X is similar to the Cisco ASR 1000 in terms of the software release that it runs on the system.
Q. Are the Cisco ASR 1000 Shared Port Adapter (SPA) cards supported on the Cisco 4451-X?
A. No. SPAs are not compatible with the Cisco 4451-X.
Q. Can the NIMs or service modules available on the Cisco 4451-X work on the Cisco ASR 1000?
A. Neither NIMs nor service modules will work with the Cisco ASR 1000 Series.
Q. Can I use the enhanced high-speed WAN interface cards (EHWICs) available on the Cisco 1900, 2900, and 3900 Series ISRs on the Cisco 4451-X?
A. EHWIC modules available on the Cisco Integrated Services Routers Generation 2 (ISR G2) routers will not work with the Cisco 4451-X. The Cisco 4451-X is targeted at high-end branch-office environments, making most EHWICs unapplicable. Also, the newer NIM architecture allows for faster, more capable modules on a high-end platform.
Q. Can I use the NIMs on the Cisco 1900, 2900, and 3900 Series ISRs?
A. No. NIMs are designed for a newer architecture and will not work on the Cisco 1900, 2900, and 3900 Series Routers.
Q. Can I use the Cisco Unified Computing System ™ (Cisco UCS ®) E-Series Service Modules available on the Cisco 2900 and 3900 Series ISRs on the Cisco 4451-X?
A. Yes, the Cisco UCS E-Series Modules are supported on the Cisco 4451-X.
Q. Can I use the Cisco Enhanced Service T3/E3 module (SM-X-1T3/E3) available on the Cisco 2900 and 3900 Series ISRs on the Cisco 4451-X?
A. Yes, the Cisco Enhanced Service T3/E3 module SM-X-1T3/E3is supported on the Cisco 4451-X.
Q. What memory upgrade options are available on the Cisco 4451-X?
A. The Cisco 4451-X has separate data and control-plane memory. The control-plane memory comes as 4 GB default, upgradable to 16 GB. The data-plane memory comes as 2 GB default and is not upgradable today.
Q. How many dual inline memory modules (DIMMs) does the Cisco 4451-X have?
A. The Cisco 4451-X has three DIMM slots. Two slots are used for control-plane and one slot for data-plane memory.
Q. In the case of control-plane memory, can I put, say, a 4-GB DIMM in one slot and a 2-GB DIMM in the other slot?
A. No. Like the Cisco 3900 Series, the Cisco 4451-X expects both the DIMM slots to have the same size of memory; that is, either 4-GB memory in both slots, making the control-plane memory size total 8 GB, or 2-GB memory in both slots, making the control-plane memory size total 4 GB. This setup is necessary because these platforms interleave memory devices for faster access.
Q. Do all four ports with both RJ-45 and Small Form-Factor Pluggable (SFP) FPGE connections support failover?
A. No. The four front-panel GigabitEthernet ports do not support auto failover. The default media-type is RJ-45 and the user has to manually change the media-type to SFP so that the SFP connection comes up.
Q. Is MDI crossover (MDI-X) supported on the four onboard RJ-45 Ethernet interfaces?
Q. What type of backplane is used between components in the Cisco 4451-X?
A. The Cisco 4451-X uses the Multigigabit Fabric (MGF) for Layer 2 connectivity between the modules. The MGF can provide either 2 Gbps to all NIM slots or up to 10 Gbps to all SM-X slots. The MGF is completely nonblocking and can forward in excess of 50 Gbps.
Q. What power cables work with the Cisco 4451-X?
A. All power-supply options for the Cisco 4451-X use a standard IEC C13 connector. No special IEC C15 cord is necessary for the Power over Ethernet (PoE) power supply, unlike the Cisco 3900 Series because higher-efficiency power supplies (85 percent) are used in the Cisco 4451-X. This cord thus helps lower the maximum current these power supplies can draw.
Q. Are the Cisco 4451-X power supplies field replaceable units (FRUs)?
A. Yes. The power supplies can be replaced in the field.
Q. Are the Cisco 4451-X power supplies hot-swappable?
A. Yes. You do not need to power down the chassis to insert or remove a power supply. Also, unlike the Cisco 3900 Series, the bezel and fan tray can remain in place while a power supply is replaced.
Q. Does the Cisco 4451-X have a DC power-supply option?
A. No, there is no DC power-supply option for the Cisco 4451-X at first customer shipment (FCS). This enhancement is planned for future deployments.
Q. What are the power options for PoE on the Cisco 4451-X?
A. The Cisco 4451-X has two PoE options. Two of the FPGE interfaces can be powered with the addition of a dedicated power-conversion module installed into the system (PWR-GE-POE-4400). This module does not require a higher-capacity system power supply and will work with the default 450W power supply. The PoE power for the FPGE ports is completely independent from PoE power to the rest of the system.
The Cisco 4451-X also has the option of a PoE power supply to provide PoE power to modules in the system such as an Ethernet switch module. This power supply actually includes two components as a single part: a higher-capacity 1000W system power supply and a PoE conversion module that converts system power into PoE for modules within the system. The Cisco 4451-X can accept up to two PoE power supplies and power-conversion modules for redundant operation or PoE Boost Mode.
Q. What is the difference between PoE Redundancy Mode and PoE Boost Mode?
A. Both modes require that two power supplies be installed in the Cisco 4451-X. Redundancy mode provides 500W of PoE power to the chassis - the maximum amount a single power supply can offer - meaning that if a power supply fails the second power supply will be able to continue to deliver 500W of PoE power. PoE Boost Mode provides 1000W of PoE power - the maximum amount of power from both power supplies combined - meaning that if a single power supply fails the second redundant power supply will be able to provide only 500W of PoE power, cutting the amount of PoE power available by half.
Q. With redundant power supplies can we switch the power to primary when it fails and the router is running on secondary power supply?
A. There is no concept of primary or secondary power supply for the Cisco 4451-X. The power supplies are simply redundant and when one fails the other power-supply unit (PSU) takes over by transparently providing power to the entire system. No switching or intervention is required. Both share the load when running in the system; however, when one fails the other provides power to the complete unit. When the failed PSU is replaced with the new PSU in the system, the two power supplies are redundant.
Q. Are the PoE interfaces PoE+?
A. PoE+ is available on the new SM-X Ethernet switch modules as well as on the FPGE ports.
Q. How does the system fan speed vary?
A. The Cisco 4451-X uses both an inlet temperature and an altitude sensor to determine the best fan-speed setting. There are four different inlet temperature ranges and five different altitude ranges for a total of 20 possible different fan-speed settings. The addition of an altitude sensor is an industry first for a branch-office platform. With altitude data incorporated into the fan speed, the system can account for the density of air cooling in order to select the most efficient, and quietest, fan-speed setting. All system fans run at the same speed.
Q. Can the Cisco 4451-X handle the failure of a fan?
A. Yes. A fully loaded system will function normally below 6000 feet (1.82 km) with a single fan failure. In the case where the Cisco 4451-X is above 6000 feet and in 32ºF (40ºC), it may shut down because of overheating. The system is rated to operate in 32Fº at up to 10,000 feet (3.05 km).
Failure of a power-supply fan will likely result in overheating and shutdown of the power supply. If power redundancy is required, you should install two power supplies.
Q. Do we have the airflow cubic-feet-per-minute (cfm) measurements for the fan on the Cisco 4451-X?
A. The airflow information for the Cisco 4451-X follows:
● Maximum: 125 cfm
● Typical: 56 cfm
Q. Is a rack-mount kit available for the Cisco 4451-X? How do I order it?
A. Yes. A rack-mount kit is part of the default accessory kit, and it is shipped with the Cisco 4451-X. Order part number ACS-4450-RM-19= for the spare 19-inch rack-mount kit for the Cisco 4451-X. By default the router will be shipped with this default 19-inch rack-mount kit.
Q. Is a 23-inch telco rack-mount kit available for the Cisco 4451-X?
A. Order part number ACS-4450-RM-23= for the spare 23-inch rack-mount kit for the Cisco 4451-X.
Q. How can I calculate the mean time between failures (MTBF) information for the Cisco 4451-X with the plugged-in modules? Is a MTBF calculator available, such as for the ISR G2 routers?
A. This information is not currently available.
Q. What else is part of the default accessory kit?
A. The default accessory kit includes:
● Mechanical ground lug 90 feet per screw kit 19-inch rack-mount kit
● Regulatory Compliance and Safety Information (RCSI) roadmap document
● Plastic bag
● Shipping label
● Document pointer card for Cisco 4451-X
Q. What is the purpose of the GigabitEthernet0 on the Cisco 4451-X?
A. The GigabitEthernet0 is the dedicated management port on the Cisco 4451-X. This interface connects directly to the control-plane CPU and is ideal for managing the router through Telnet, Secure Shell (SSH) Protocol, Simple Network Management Protocol (SNMP), and other management protocols. It is also ideal for downloading software images, uploading logs, and connecting to other management devices such as RADIUS, Network Time Protocol (NTP), Domain Name System (DNS), Dynamic Host Configuration Protocol (DHCP), and TACACS servers. This interface should never be used for forwarding normal data traffic through the system because every packet goes directly to the control-plane CPU, bypassing the platform data plane. Because of this sensitivity, G0 is in a dedicated Mgmt-Intf Virtual Route Forwarding (VRF) port by default. This setup prevents accidental routing mistakes that could cause data traffic to be routed to the management network.
Q. Is MDI-X supported on the management RJ-45 Ethernet interface?
Q. Is a console port available on the Cisco 4451-X?
A. The Cisco 4451-X has the option of the regular RJ-45 console port as well as the USB console port. As with the ISR G2 routers, only one console port can be used at a time, with preference given to the USB console port.
Q. Is online insertion and removal (OIR) supported on the Cisco 4451-X?
A. Yes, OIR is supported on the Cisco 4451-X for the following scenarios:
● Surprise insertion or removal of any NIM in any of the NIM slots
● Surprise insertion or removal of any SM-X in the SM-X slots
● Surprise insertion or removal of any power supply or system PoE conversion module
● Surprise replacement of the system fan tray; note, however, that this replacement must take place quickly enough that the system does not overheat, and depending on altitude and ambient temperature, the amount of time can vary greatly
Note that SM-X and NIM modules allow replacement only for like-to-like modules. A faulty module can be replaced with a good module of the same type but cannot be replaced with a completely different module of a different type.
Q. Will the NIMs and service modules continue to function as they normally do after OIR on the Cisco 4451-X?
A. Yes, provided the OIR was carried out using a like-for-like module.
Q. What type of Cisco IOS Software is available for the Cisco 4451-X?
A. The Cisco 4451-X runs the same feature-rich Cisco IOS XE Software as the current-generation Cisco ASR 1000 Series. By using the same software release as the Cisco ASR 1000 Series, the Cisco 4451-X benefits from a rich history of branch-office feature development as well as ongoing feature development.
Q. What software options are available for the Cisco 4451-X?
A. One change that customers like is the Cisco IOS Software images available on the ISR G2 routers, which reduce numerous software images into one. Therefore, the Cisco 4451-X has a single Cisco IOS XE Software image. This image is known as a universal image. It contains all features and functions in a single software image. You can selectively enable functions within this universal image by using Cisco Software Activation Licenses that activate capabilities within that image. You now need only a single Cisco IOS XE Software image for the router regardless of the features or functions you need for any particular area in your network.
Q. What is a universal image?
A. For the Cisco 4451-X, Cisco IOS XE Software is delivered in a single universal Cisco IOS XE Software image per platform for each release. With the universal image you need to choose only the Cisco IOS XE Software release you need for your network. With the Cisco 4451-X, the universal image includes all features and options.
Cisco Software Activation is used to enable feature packages such as, for instance, the Security, Application Experience, or the Unified Collaboration technology package. This new model greatly simplifies the effort required to track license compliance across a large number of devices and reduces the number of images that must be supported in a network. Simultaneously, the number of feature packages is also greatly simplified so that now only major feature packages, including the IP Base default package, are available with a single universal image.
Q. What does the software packaging and licensing model look like for the Cisco 4451-X?
A. The Cisco 4451-X has packaging and licensing similar to that of the Application Experience routers (refer to Figure 1):
● IP Base Technology Package (default)
● Application Experience Technology Package (AppX)
● Security Technology Package (SEC) and High Security (HSEC) for strong encryption throughput and tunnel count
● Unified Collaboration Technology Package (UC)
Packaging and License Model for Cisco 4451-X
Q. Is the software packaging on the Cisco 4451-X similar to that for the ISR G2, which is Right-To-Use (RTU)-based?
A. The Cisco 4451-X has software packaging similar to that of the ISR G2, and it is RTU, also known as honor-based. A 60-day evaluation license for all features is included with every Cisco 4451-X. After 60 days, an evaluation license automatically converts to a RTU license. At that point, it is expected that a RTU license will be purchased for that feature on that platform. This model is the same as that for the ISR G2.
Q. What about export and import requirements for strong encryption?
A. The strong enforcement of encryption capabilities provided by Cisco Software Activation satisfies requirements for the export of encryption capabilities, so non-k9 images are no longer needed. However, some countries have import requirements that require the release of the source code for strong payload (VPN) encryption features. To satisfy the import requirements of those countries, a universal image that lacks strong payload encryption is available. This image is identified by the “universalk9_npe” designation in the image name. The universal image with strong payload encryption is recognized by the “universalk9” tag. This image satisfies both import and export requirements for virtually all countries.
Q. Is a High Security (HSEC) license offered on the Cisco 4451-X to achieve greater cryptographic tunnel count and throughput?
A. Yes, an HSEC license is required to achieve more than 225 cryptographic tunnel count and 170 Mbps of total IP Security (IPsec) throughput (bidirectional traffic).
Q. What is an HSEC license?
A. An add-on license above the Security (SEC) technology package license, known as HSEC, provides export controls for strong levels of encryption. HSEC is available to customers in all currently nonembargoed countries as listed by the U.S. Department of Commerce. Without an HSEC license, SEC performance is limited to 225 tunnels and a total of 170 Mbps of IPsec throughput. An HSEC license removes this limitation. Because of these export control requirements, the HSEC license is the only license on the Cisco 4451-X that requires installation of a license key file to activate. In other words, HSEC is not a RTU license.
Q. What types of licenses are available for the Cisco ISR G2 routers?
● Permanent: A permanent license never expires. When a permanent license is installed on a system, it is good for that feature set for the life of the router, even across Cisco IOS XE Software releases. For example, when a Unified Collaboration, Security, or Application Experience (AppX) license is installed on a system, the subsequent features for that license are activated even if the system is upgraded to a new Cisco IOS XE Software release. A permanent license is the most common license type used when you purchase a feature set for a device.
● Temporary: A temporary license, sometimes referred to as an evaluation license, is good for a limited amount of time. The Cisco 4451-X includes a full set of 60-day temporary licenses for the AppX, Unified Collaboration, and Security feature sets. You can activate and deactivate these licenses at any time to evaluate a feature set before making the decision to purchase and upgrade to a permanent license. You also have some flexibility when you need to upgrade to a permanent license.
● Only the time a temporary license is active is counted against the available time on the license. When a temporary license expires, you cannot extend it. However, in extreme cases the Cisco Technical Assistance Center (TAC) can issue new emergency temporary licenses to aid in troubleshooting a problem.
● Counted: A counted license actually counts something in the system. A typical example is the number of Cisco Unified Border Element or SRST Licenses possible on a system. These licenses are analogous to the counted paper licenses used with systems in the past. However, the new Cisco Software Activation infrastructure greatly simplifies the management of these licenses.
Q. Is hardware or software high availability supported on the Cisco 4451-X?
A. The Cisco 4451-X does not support hardware or software high availability.
Q. Is the Cisco Locator/ID Separation Protocol (LISP) supported on the Cisco 4451-X?
A. Yes, LISP is supported on the Cisco 4451-X.
Q. Is In-Service Software Upgrade (ISSU) supported on the Cisco 4451-X?
A. ISSU is not supported on the Cisco 4451-X.
Q. Is Suite-B or Next-Generation Encryption (NGE) support available on the Cisco 4451-X?
A. Yes, Suite-B and NGE support is available on the Cisco 4451-X as part of the initial release.
Q. Is SSLVPN supported on the Cisco 4451-X?
A. No. The Cisco 4451-X does not support SSLVPN.
Q. What VPN methods are supported on the Cisco 4451-X?
A. The Cisco 4451-X supports all current and any new VPN technologies such as Easy VPN, Group Encrypted Transport VPN, Dynamic Multipoint VPN (DMVPN), and Cisco IOS FlexVPN that are supported on the ISR G2 or ASR 1000 Series.
Q. Is the intrusion prevention system (IPS) supported on the Cisco 4451-X?
A. No, IPS is not supported on the Cisco 4451-X.
Q. Is content filtering supported on the Cisco 4451-X?
A. Content filtering is presently not supported on the Cisco 4451-X.
Q. Is the Cisco Cloud Web Security (ScanSafe) connector supported on the Cisco 4451-X?
A. Cloud Web Security (ScanSafe) is planned for a software release on the Cisco 4451-X in a later release.
Q. Is the Cisco 4451-X Network Equipment Building System (NEBS) certified?
Q. Does the Cisco 4451-X have certifications such as Common Criteria and Evaluation Assurance Level 4 (EAL4)?
A. Common Criteria and EAL4 certification will be available shortly after FCS.
Q. Is the Solid State Drive SSD or hard-drive carrier card field upgradable or replaceable?
A. Yes, the carrier card is field replaceable, with some restrictions in the first release where only the third NIM slot supports it. This restriction will, however, go away in a future release.
Q. In what form factors are the serial interface NIMs available? What is the maximum serial density on the Cisco 4451-X?
A. The new NIM module type allows for a wide range of port densities for T1/E1 interfaces including 1, 2, 4, and 8 ports. A smart serial NIM will be available in 1-, 2-, and 4-port versions shortly after initial release of the Cisco 4451-X.
Q. Is OIR possible on the hard disk drive (HDD)?
Q. Is there a service module adapter available which will support hosting of any of the older network modules?
A. The older network modules are not supported on the Cisco 4451-X.
Q. What is the maximum number of SSD drives that can be present in the NIM-SSD? Do they work in a redundant fashion?
A. There can be two drives as part of the NIM-SSD. They do not work in a redundant fashion in the initial release.
Q. Is there a channelized solution on the Cisco 4451-X?
A. There is a channelized solution available on the T1/E1 interfaces. There is no channelized solution available on the T3/E3 module.
Cisco UCS E-Series Module
Q. Are the Cisco UCS E-Series modules supported on the Cisco 4451-X?
A. Yes. The Cisco UCS E140S, UCS E140D, UCS E140DP, UCS E160DP, and UCS E160DP modules are all supported on the Cisco 4451-X.
Q. Can we run Cisco virtual Wide Area Application Services (vWAAS) for larger-scale WAAS deployments on the Cisco UCS E-Series?
A. Yes, vWAAS supports up to 6000 TCP connections on the Cisco UCS E-Series. Additionally, standard VMware Virtual Machines can co-exist with vWAAS, allowing the Cisco UCS E-Series module to be used for branch-office server consolidation.
Q. Are SSD drives supported on the Cisco 4451-X?
A. Yes, the SSD drives on both a NIM-SSD for onboard services as well as the Cisco UCS E-Series module.
Q. Will WAAS performance be software licensed?
A. The Application Experience license, included with the AX bundle, includes a license for up to 2500 TCP connections. This model can be supported with WAAS integrated into the Cisco 4451-X. For additional scale, a Cisco UCS E-Series module can be added to run vWAAS. Integrated AppNav functions in the Cisco 4451-X allows the pooling of these WAAS resources to make the most efficient use of all.
Q. What technology license is required for AVC?
A. The Application Experience (AppX) technology package is required for using the AVC feature set. The AVC solution encompasses Network-Based Application Recognition 2 (NBAR2), Flexible NetFlow, Media Monitoring, and Application Response Time metrics.
Q. What WAN optimization solutions are available on the Cisco 4451-X?
A. ISR WAAS is available as an application that can run within a virtual container on the Cisco 4451-X. One other option is to run the vWAAS on the Cisco UCS E-Series module.
Q. Is NIM-SSD necessary to run applications such as ISR-WAAS on the Virtual Container?
A. Yes, NIM-SSD is required to run applications such as ISR-WAAS.
Q. Is AppNav available on the Cisco 4451-X?
A. Yes AppNav is available on the Cisco 4451-X.
Q. Is the Web Cache Control Protocol (WCCP) available on the Cisco 4451-X?
A. WCCP is available on the Cisco 4451-X, and we recommend that you use AppNav for WAN optimization deployments.
Q. Is Cisco WAAS Express one of the WAN optimization solution options on the Cisco 4451-X?
A. Cisco WAAS Express is not available on the Cisco 4451-X. The integrated ISR-WAAS solution includes full WAAS functions without compromise.
Q. Is the support for Survivable Remote Site Telephony (SRST) and Cisco United Border Element (UBE) functions on the Cisco 4451-X when it is launched?
A. Yes, support for SRST and Cisco UBE is part of the Cisco 4451-X when it is launched.
Q. Is Cisco Unified Communications Manager Express (Unified CME) supported on the Cisco 4451-X?
A. Cisco Unified Communications Manager Express is not supported on the Cisco 4451-X presently. This support may be available in a future release.
Q. For the case where we have digital signal processor (DSP) conferencing will we have similar functions as the videoconferencing feature on the ISR G2 routers? How will it scale?
A. At this time there is no support for videoconferencing on the Cisco Packet Voice Data Module 4 (PVDM4) DSPs correct.
Q. Where do I insert PVDMs on the Cisco 4451-X?
A. You can insert PVDMs on both the motherboard and directly on some NIMs, depending on the use case. Cisco UBE requires that PVDMs be installed on the motherboard, whereas time-division multiplexing (TDM) deployments require them to be installed directly on the NIM. Unlike the ISR G2 routers, the Cisco 4451-X does not have a TDM domain on its motherboard.
Q. How many PVDM slots are present on the motherboard?
A. There is only one PVDM slot on the motherboard.
Q. Can the TDM cards use the motherboard PVDMs?
Q. What version of Cisco Configuration Professional supports the Cisco 4451-X?
A. Cisco Configuration Professional Version 2.7 supports the Cisco 4451-X.
Q. Is Cisco Security Manager supported on the Cisco 4451-X?
A. No. Cisco Security Manager support is not available for the Cisco 4451-X.
Q. What version of the Cisco Prime enterprise and service provider management application supports the Cisco 4451-X?
A. Cisco Prime 2.0 supports the Cisco 4451-X.
Q. Does the Cisco Configuration Engine support the Cisco 4451-X?
A. Support for the Cisco 4451-X is available on the Cisco Configuration Engine.
More Related Cisco ISR 4451-X and Other Cisco ISR G2 Tips:
Cisco Catalyst 6880-X is a highly scalable and manageable solution for user access offering up to 1008 (FCS) 10/100/1000 ports within a single management system when working with the Catalyst 6800ia remote linecard, while providing the same feature set as a regular Catalyst 6500 that you might be longing for. What do you need to know about Cisco 6880-X? We will summarize some main highlights for you.
The Cisco Catalyst 6880-X and Port cards
Chassis-Cisco 6880-X Series
- 6880-X comes in two flavors
- C6880-X-LE (Lite) with smaller hardware table
- C6880-X (Heavy) with larger hardware table
- Single fixed Supervisor (based on SUP2T)
- Require minimum IOS 15.1SY with feature parity to SUP2T
- Capable of 220 Gbps/Slot. Total of 2Tbps. 4Tbps in VSS.
- Built-in 16 x 10G (10/100/1000 with Copper SFP or 1G/10G with SFP/+)
- 80 Gbps to backplane (ie. 2:1 Oversubscription)
- Based on WS-X6904-40G (also support up to 16 x 10G)
- Can disable second half of port ASIC to enable line rate (Performance Mode)
- Four half-width expansion slots available
- Dimension 8.5x 17.36 x 23 inches, Height = 4.85 RU
- Dual 3KW Power Supply
- Side-to-side airflow
Linecard-Catalyst 6880-X Switches
- 16-Port 10G Module
- Also comes with two flavors
- C-6880-X-LE-16P10G (Lite) with smaller hardware table
- C-6880-X-16P10G (Heavy) with larger hardware table
- 16 x 10G (10/100/1000 with Copper SFP or 1G/10G with SFP/+)
- 80 Gbps to backplane (ie. 2:1 Oversubscription)
- Based on WS-X6904-40G (also support up to 16 x 10G)
- Can disable second half of port ASIC to enable line rate (Performance Mode)
- In other word, this is identical to the built-in ports
- Linecard type can be mixed with chassis type but they will operate at the lowest common denominator, hence not recommended.
Catalyst 4500X vs. Cisco 6880-X
If you are familiar with Catalyst 4500X, you can see that they have a lot of similarity, being able to support 1G/10G on all ports, and VSS capable. Since 4500X max out at 40 ports, if you have a need to exceed that, 6880-X could certainly be your option by scaling up to 80 ports. Despite the 2:1 oversubscription of 6800-X, the benefit of centralized configuration with 6800ia can be very compelling. Finally, the lack of modularity and redundancy of the Supervisor can easily be overcome by deploying VSS.
More Related Cisco Switch Topics: