Posts with #cisco routers tag
The CCNA might be intimidating at first, especially since Cisco has expanded the scope of the exam to include more advanced topics such as Open Shortest Path First (OSPF) routing which is traditionally only tested in the CCNP and other professional level exams. Time management during the exam is the number 1 most important thing to do well. This means scoring easy points when possible and to spend more time focusing on those questions which are harder.
To maximize the chance of passing the CCNA exam, here are 2 most important (in my opinion) topics to focus on for the CCNA:
Learning how to subnet effectively is the most important thing for the CCNA. It’s also important to be able to size subnets quickly in the real world for network planning and troubleshooting purposes. Because the CCNA (and any other certification exam) is a test of your time management skills during the test, and subnetting can be done quickly (and 100% correctly) if you know the right technique, it’s a quick way to score easy points.
Common subnetting questions include calculating the number of hosts in a subnet, finding if 2 hosts are in the same subnet, and deciding on the correct hostmasks, among others. Being able so solve such questions quickly means that you will be able to free up valuable exam time to solve other questions. Answering such calculation questions are a matter of simple calculations and it’s hard to get them wrong once you know how. Again, the key is speed and you will definitely want to get subnetting questions out of the way as quickly as possible.
Simulation questions (commonly now referred to as “sims”) are designed by Cisco to test the practical aspect of Cisco networking. A simulation of a real Cisco IOS command-line is provided to you and you are expected to troubleshoot or otherwise configure the network to the required specification.
These questions are more time consuming but very important. Only Cisco knows for sure how these are actually scored but it’s very likely that you won’t get enough points to pass the CCNA if you cannot answer all the simulation questions to a satisfactory level. The CCNA passing score gets higher all the time, which makes scoring high on the simulation questions a priority.
One good thing about using simulation questions is that you’ll be able to gauge roughly how well you’ve done by showing the running configuration and running other tests such as ping and using other show commands. A good way to prepare for the exam is to use a Cisco router simulator.
More guide and tips about CCNA: Best Path for Getting Your CCNA Certification
The Cisco 1941W Integrated Services Router (ISR) delivers highly secure data, mobility, and application services.
Cisco 1941W is a true solution in terms of delivering pure security for your transmitted data, application as well as for security of your mobility over wired or especially designed wireless network whether it is at home or the network is prepared for your small office. This ISR router of 1900 series has Ethernet ports (2 same ports) of 10Mbps, 100Mbps and 1000Mbps speed.
Cisco 1941W router also comes with (e)HWIC’s 2 slots that are able of supporting or hosting 1 single wide Enhanced High-Speed WAN Interface Card as well as of 2 single wide or you may say 1 double wide card. Wireless Access Point is also supported by 1941W router through built-in 802.11n technology. Power distribution is also fully integrated to this router just to support Cisco Enhanced Power of Ethernet as well as 802.3a PoE.
VPN encryption through accelerated hardware (embedded hardware rather) is also supported by Cisco 1941W Integrated Services Router and this 1900 series’ router has identity management support as well which is normally done through public key infrastructure’s usage as well as through the usage of authorization, authentication and accounting method i.e. “AAA”.
Integrated threat control functionality of Cisco 1941W is as same as it is seen in 1941 router of 1900 series who provides it (threat control functionality) through IOS IPS of Cisco, IOS Zone-Based Firewall of Cisco, IOS Content Filtering of Cisco and finally IOS Firewall of Cisco. Mobility in this router is supported through 5 GHz mode of 802.11a/n as well as through 2.4 GHz mode of 801.11/b/g/n of radio signals.
Quick View: Key features of Cisco 1941W include:
- 2 integrated 10/100/1000 Ethernet ports
- 2 Enhanced High-Speed WAN Interface Card slots that can host 2 single wide or 1 double wide and 1 single wide (e)HWIC
- 1 integrated 802.11n Wireless Access Point
- Fully integrated power distribution to modules supporting 802.3af Power over Ethernet (PoE) and Cisco Enhanced PoE
- Embedded hardware-accelerated encryption for VPN
- Secure collaborative communications with Group Encrypted Transport VPN, Dynamic Multipoint VPN, or Enhanced Easy VPN
- Integrated threat control using Cisco IOS Firewall, Cisco IOS Zone-Based Firewall, Cisco IOS IPS, and Cisco IOS Content Filtering
- Identity management that uses authentication, authorization and accounting (AAA), and public key infrastructure
- The integrated access point offers IEEE 802.11n draft 2.0 support for mobile access to high-bandwidth data, voice, and video
- The access point supports both unified and autonomous deployments and is supported by a wireless LAN controller and the Cisco Wireless Controller System
- IEEE 802.11n technology delivers outstanding reliability and up to nine times the throughput of current IEEE 802.11 a/b/g networks
- Dual radios for 2.4-Ghz 802.11b/g/n. and 5-GHz 802.11a/n modes
Caskibum’s Problem of Opening Port 873 on Cisco 1921
I have a Cisco 1921 and need to open ports 22 (SSH) and 873 (rsync) to run an rsync server on my network and the rest of the network needs standard "internet" access. I am fairly new to Cisco ACLs and so I expect I'm doing something stupid but not sure what. When I add the ip access-group XXX in / out to the gig0/0 interface, I lose all www functionality at that point. Here is my current (working) config with the ACLs listed (101 and 102) but not enabled on the gig0/0 interface. I have tried the "established" statement at the start and end of the 101 list, no difference. Thanks for any help!
Current configuration : 2675 bytes
! Last configuration change at 15:03:45 UTC Sun Dec 18 2011 by
service timestamps debug datetime msec
service timestamps log datetime msec
enable secret 5 $1$Sx2k$wiHT8Af585IB/HsSZkwC61
enable password 7 073E325F19190C1D47
no aaa new-model
no ipv6 cef
no ip dhcp use vrf connected
ip dhcp excluded-address 10.1.0.1 10.1.0.149
ip dhcp excluded-address 10.1.0.200 10.1.0.254
ip dhcp pool net_dhcp
network 10.1.0.0 255.255.255.0
lease 0 0 5
no ip domain lookup
ip domain name treeskier.ca
multilink bundle-name authenticated
license udi pid CISCO1921/K9 sn FGL15092836
username blah password blahblah
ip ssh version 2
ip dhcp client update dns
ip address dhcp
ip nat outside
! ip access-group 101 in
! ip access-group 102 out
! once I turn these on, it all dies.
no cdp enable
no mop enabled
ip address 10.1.0.1 255.255.255.0
ip nat inside
no mop enabled
ip forward-protocol nd
ip http server
ip http authentication local
no ip http secure-server
ip nat inside source list 1 interface GigabitEthernet0/0 overload
ip nat inside source static tcp 10.1.0.102 873 interface GigabitEthernet0/0 873
ip nat inside source static tcp 10.1.0.102 22 interface GigabitEthernet0/0 22
access-list 1 permit 10.1.0.0 0.0.0.255
access-list 1 remark INSIDE_IF=gig0/1
access-list 101 permit tcp any 10.1.0.0 0.0.0.255 established
access-list 101 permit tcp any host 10.1.0.102 eq 22
access-list 101 permit udp any host 10.1.0.102 eq 22
access-list 101 permit tcp any host 10.1.0.102 eq 873
access-list 101 permit udp any host 10.1.0.102 eq 873
access-list 102 permit tcp 10.1.0.0 0.0.0.255 any
access-list 102 permit udp 10.1.0.0 0.0.0.255 any
dialer-list 1 protocol ip permit
banner login ^C**************************^C
CON and VTY setup
scheduler allocate 20000 1000
A bit of really basic troubleshooting:
Standard IP access list 1
10 permit 10.1.0.0, wildcard bits 0.0.0.255 (9854736 matches)
Extended IP access list 101
10 permit tcp any 10.1.0.0 0.0.0.255 established
20 permit tcp any host 10.1.0.102 eq 22
30 permit udp any host 10.1.0.102 eq 22
40 permit tcp any host 10.1.0.102 eq 873
50 permit udp any host 10.1.0.102 eq 873
Extended IP access list 102
10 permit tcp 10.1.0.0 0.0.0.255 any
20 permit udp 10.1.0.0 0.0.0.255 any
Router#sh ip nat translations
Pro Inside global Inside local Outside local Outside global
tcp 192.168.0.10:22 10.1.0.102:22 --- ---
tcp 192.168.0.10:873 10.1.0.102:873 --- ---
tcp 192.168.0.10:54693 10.1.0.150:54693 126.96.36.199:80 188.8.131.52:80
tcp 192.168.0.10:54695 10.1.0.150:54695 184.108.40.206:80 220.127.116.11:80
tcp 192.168.0.10:54696 10.1.0.150:54696 18.104.22.168:5222 22.214.171.124:5222
tcp 192.168.0.10:54699 10.1.0.150:54699 126.96.36.199:1935 188.8.131.52:1935
tcp 192.168.0.10:54700 10.1.0.150:54700 184.108.40.206:80 220.127.116.11:80
... (more dynamic NAT at work)
Reply to Caskibum from Imbadatthis
You aren't allowing DNS in .
also a nice to know:
After Imbadatthis ‘s Reply
Caskibum solved problems like this:
Thanks for the response.
I actually sorted it out last night, my "new" cable modem was blocking the port forwarding before it got to the router. So once I set up the NAT port forwarding on the cable modem, all good now.
Just FYI, I've ended up with a much simpler ACL and NAT setup:
ip nat inside source list nat-acl interface GigabitEthernet0/0 overload
ip nat inside source static tcp 10.1.0.101 873 interface GigabitEthernet0/0 873
ip nat inside source static tcp 10.1.0.101 22 interface GigabitEthernet0/0 22
ip access-list extended nat-acl
permit ip 10.1.0.0 0.0.0.255 any
permit tcp any host 10.1.0.101 eq 22
permit tcp any host 10.1.0.101 eq 873
More discussion between these two buddies to talk about Opening port 873 on Cisco 1921
Imbadatthis: So you've removed both acl 101 and 102?
Yep, the only ACL is the named extended list, which is applied on the outside interface in the overload command. I could have probably left them in place, I found this "alternate" solution with the named extended list as it is now, and then after that didn't work either I went to the cable modem and found the source of the problem. I expect the 101 / 102 acls are fine if I were to use them. Then the two static NAT commands to handle the traffic direction. Seems to be working. I'm no security expert so if this leaves some gaping hole please let me know and I'll rework it.
Ideal for Enterprise WAN aggregation or service provider environments, Cisco 7600 series is the industry's first carrier-class edge router to offer integrated, high-density Ethernet switching, carrier-class IP/MPLS routing, and 10-Gbps interfaces, benefiting enterprises and helping enable service providers to deliver both consumer and business services over a single converged Carrier Ethernet network.
The Cisco 7600 Internet Router delivers optical wide- and metropolitan-area network (WAN and MAN) services with high-touch IP services at the network edge. Now, service providers (SPs) and enterprises can "service enable" their networks at optical speeds, providing competitive advantage and service differentiation to the SP and high-speed connectivity and link usage efficiency to the enterprise.
Cisco 7600 Router’s Key Features
High performance, with up to 720 Gbps in a single chassis, or 40 Gbps capacity per slot
A choice of form factors purpose-built for high availability
Cisco I-Flex design: A portfolio of shared port adapters (SPAs) and SPA interface processors (SIPs) that controls voice, video, and data experiences
Scalable and extensible suite of hardware and software capabilities to enable intelligent Carrier Ethernet services
Integrated Video Call Admission Control with innovative visual quality of experience for both broadcast and video on demand (VoD)
Intelligent Services Gateway, providing scalable subscriber and application awareness with multidimensional identity capabilities and policy controls
Integrated Session Border Control with quality of experience in both Session Initiated Protocol (SIP) and non-SIP applications
What Cisco 7600 series Supports
Supports Services modules such as IPsec, firewall, SSL VPN
Intrusion Prevention System (IPS) Modularity
Chassis supports up to 4-, 6-, 9-, and 13-slot chassis for redundant supervisors and line cards
Supervisor engines supporting up to 15 Mpps with broad range of edge services
Support for Shared Port Adapter (SPA) and SPA Interface Processors (SIP), which offers intelligent services.
Supports up to 12 SPA bays
Support for the Enhanced FlexWAN module, which offers Port Adapter investment protection
Cisco 7600 Router’s Price & Availability
Cisco 7600 series ranges from US$5000 to US$20000, not all the types are required by enterprise head offices. There are some 7600 series items such as Cisco 7606, Cisco 7609, Cisco 7609-S, Cisco 7606-S; these are popular among large enterprises. Prices of Cisco 7606 and Cisco 7609 are available here:
CISCO7606: List price: US$6,000.00 / Wholesale Price: US$2,940.00
CISCO7609: List price: US$10,500.00 / Wholesale Price: US$5,145.00
CISCO7606-S: List price: US$6,000.00 / Wholesale Price: US$2,940.00
CISCO7609-S: List price: US$10,500.00 / Wholesale Price: US$5,145.00
If you want to know more pricing and purchasing information of Cisco router and other Cisco IT equipments, you can visit Cisco router at Router-switch.com…
The Cisco Aironet 1242 is a wireless access point created by Cisco. The main difference between this device and most other Cisco products is that the Aironet1242 provides support for mesh wireless networks. Mesh networks extend wireless network range by relaying information from an access point to other access points, instead of requiring that each access point have its own wired backbone connection.
Ethernet cable you first need
Instructions to Use the Cisco Aironet 1242
1. Power on the 1242.
2. Connect your network switch to the "Ethernet" port on the back of the 1242, using the Ethernet cable.
3. Log in to any computer connected to the same network switch. Click "Start," then "Programs." Select "Accessories" and "Telnet." A new Telnet window will come up.
4. Click "Connect," then "Remote system" on the Telnet window. Type the Internet Protocol (IP) of the 1242; the default is 192.168.1.1. Click "Connect."
5. Type the following commands into the Telnet session to configure an IP address for the 1242:
IP address 192.168.40.9 255.255.0.0
Replace "192.168.40.9" and "255.255.0.0" with the IP address and network mask, respectively, assigned to the 1242 by your network's administrator. Press "Enter" after each command.
6. Launch a Web browser on the computer and navigate to the Web address "http://192.168.40.9" (replace the IP address with the one assigned in Step 5). Type "Cisco" as the user name and "Cisco" as the password, then press "Enter." The 1242's configuration utility will come up on the browser.
7. Click "Express Set-up." Type a host name of your choice if the default value is already being used by another 1242 on the same network. Select "Enable" for the "Aironet Extensions" for both the 802.11a and the 802.11g radios. Click "Apply." At that point, the 1242 will provide a wireless network ready for client computers to join.
More Related: Password Recovery on Cisco 1242 Access Point
Main Feature of IPv6
IPv6 address a lot concerns and issues that are faced today in using IPv4. Cisco CCNA Certification requires that a candidate must have a general overview of IPv6 and what new features it brings into the world of networking. Here we will go through some of the features of Internet Protocol Version 6 (IPv6).
The main feature of IPv6 are described in the sections below
Larger Address Space
IPv6 addresses are 128-bits long which gives us a theoretical address space of 3.4 x 1038 addresses, like IPv4 some address space is reserved for special purpose but still there is a huge number of public routable addresses.
A larger address space allows for large address allocations to ISPs and Organization. This allows them to use a single prefix for the entire network making summarization easy and flexible which turn promotes efficient and scalable routing.
New Improved Header Format
Optional and non-essential fields are removed from the IPv6 Header and are moved the Extension Header that is placed after the IPv6 Header. Fewer fields of fixed lengths mean Header overhead is minimized and processing performance is improved. Another significant enhancement is that all routers in a path do need to do checksum recalculation for an IPv6 Packet instead error detection is handled by data-link layer technologies checksums of the end-to-end connection at transport layer.
IPv6 addresses are composed of two parts, 64-bit Network Prefix and 64-bit host part. The IPv6 address allocation follows a generally acceptable assignment policy as shown in figure 1. This allows for an efficient, hierarchical, and summarizable routing infrastructure.
Easy Address Assignment Methods
IPv6 has three assignment methods
- DHCPv6 (Stateful)
- Autoconfiguration (Stateless)
An IPv6 host can configure a link-local address for each interface automatically. By using ICMPv6 router discovery messages, a host can also determine the addresses of routers, additional addresses, and other configuration parameters.
IPSec is built into IPv6 unlike IPv4 in which it is optional. IPSec requirement is mandatory in IPv6 Protocol Suite Implementation. IPv6 networks have potentially more end-to-end security because of IPSec availability on all nodes.
New futures for IPv6 can be added through the use of Extension Headers. At present there are various Extension Headers specified for QoS, Security, Mobility and Routing purposes.
Mobility is built in to IPv6 which allows any node to use Mobile IP. Mobility is achieved using Mobility Extension Headers.
Better Quality of Service Support
IPv6 Header includes a new field called Flow Label that allows routers to identify and provide special handling for packets that belong to a particular flow. This field allows for easier identification of traffic without doing any tricks even when the packet payload is encrypted with IPSec.
Neighbor Discovery Protocol
Neighbor Discovery Protocol uses ICMPv6 messages to perform various functions such as
- Stateless Auto-configuration
- Router Discovery
- Prefix Discovery
- Address Resolution
- Neighbor Unreachability Detection
- Link MTU Discovery
- Duplicate Address Detection
- Next Hop Determination
The transition options supported by IPv6 to transition from IPv4 are another key feature of the protocol. Many Transitions mechanism are available for different scenarios. They are mentioned below
- Tunneling IPv6 over IPv4 networks
- Protocol Translation
Within each option are various different techniques to support transition. A few tunneling mechanism are mentioned below
- Static GRE Tunnels
- 6to4 Tunnels
- Automatic IPv4-Compatible IPv6 Tunnels
These rich features of IPv6 enable easy deployment, migration and operation of IPv6 networks.
Anyone can put up a web site. The hard part is helping people discover it, and then stay with it. Your first priority: Make your site people friendly. Your second: Make it search-engine friendly.
Here are a few more specific suggestions:
Design it well. Make it pleasing to the eye, and easy to navigate. If the site has a lot of pages, develop a structure that people can easily navigate, rather than throwing too many links up at once.
Write well. Re-read your text before posting it. Correct spelling and grammar errors. Use clear and concise language.
Stick to your subject(s). Don't be all over the map with content. Keep the site focused, at most, on a handful of topics that you're passionate about.
Link with words, not pictures. For web navigation, a word is worth a million pictures. A link that reads "The eternal allure of the Three Stooges" says more about the page it leads to than a photo of Larry, Moe, and Curly. That holds true for search engines as well as for people.
Use title and description tags. Search engines give priority to the text in these tags, and usually display their contents in result pages. So think carefully about what you want to put here.
Try to read your title through the eyes of a stranger. It should clearly describe the page. See the comments on this post to see how I messed up in this area.
And where do you put this text? In your page's HTML code, the title text goes between the <title>and </title> tags. The description goes inside a meta tag that looks something like this:
· <meta name="description" content="This is where you put the content of your description. It can be longer and thus more descriptive than a title." />.
Describe your images. When you do use pictures, give them descriptive file names. Also, describe the picture in the image tag's alt attribute. The Alt text is there for people who can't see the images, but it also helps search engines. In the HTML code, that tag looks something like this:
· <img src="http://urltopicture/filename.jpg" alt="Put your alt text here" />.
Finally, links can be extremely helpful in drawing people to your site. That's one of several reasons why I always suggest that people read the original forum discussion. And then I include additional links in the italicized "bio" paragraph below.
More news and info about networking you can visit: http://blog.router-switch.com/
With processing speeds up to 2 million packets per second, port- and service adapters ranging from NxDS0 to Gigabit Ethernet, and OC-3 as well as an unparalleled number of high-touch IP services, the Cisco 7200 VXR series is the ideal Services Aggregation WAN/MAN edge device for enterprises and service providers deploying any of the following solutions:
The Cisco 7200 VXR addresses these solution requirements by integrating functions previously performed by separate devices into a single platform. Through this integration, the Cisco 7200 VXR provides a single, cost-effective platform that supports:
The Cisco 7200 VXR Router Series with Network Processing Engine NPE-G2
The Cisco 7200 VXR Series offers a rich set of capabilities that address requirements for performance, density, high reliability, availability, serviceability, and manageability.
Cisco 7200 VXR Features and Benefit
Hardware for Cisco 7200 VXR Series Router includes:
More Notes: If you need to know more about Cisco 7200VXR series (for enterprise head offices and service provider edge), such as its applications, Specifications--- Cards, Ports, Slots; Components--- Chassis, Environmental Conditions; Processors, Input/Output Controllers, Port Adapter Jacket Card, Interfaces, Performance---Memory; Network Management, Power; Protocols; Product Regulatory Approvals and Compliance; Software Requirements, you can visit Cisco's official website...
Over the last several years, the technology industry has been facing a number of different challenges. This is because the sector has experienced tremendous amounts of growth that were related to the evolution of the Internet. At the same time many different consumer devices (i.e. smartphones, tablets and readers) have given everyone the power to access the latest information on the go. This has caused a number of firms to experience rapid increases in their growth rates and earnings per share.
In the case of Cisco Systems (CSCO), it has been realizing similar trends. As it has been supporting the expansion of the internet through the various routers/switches it is selling and the IT security solutions it offers. This has helped the firm to experience above average rates of growth of 10.9% in revenues and 26.6% in growth from 2009 to 2010, and remains a proverbial cash cow.
The problem is that the company has lost its focus by going into ventures that are not considered to be profitable and it has seen declining demand from its core customers. This is a common trend that occurs in some of the strongest industries (at some point in time). As this is measured through the S Curve, which states that customer needs will start to slow after periods of rapid growth. The reason why is due to the fact that the industry was able to effectively address them over the course of many years. Under this approach is when a firm will enter a period of flat to negative declines in their earnings. The reason why is because management will believe that these kinds of increases will continue on a regular basis. This is when the company will refocus its efforts in order to improve its overall bottom line numbers. As a result, Cisco has been going through a similar situation by trying to redefine itself in areas that are seeing declining customer demand.
A Tale of Two Viewpoints on Cisco
If investors are listening to Wall Street analysts, it appears as if the company has been able to make the adjustments to the changes that have taken place. Evidence of this can be seen by looking at the total number of analysts that are optimistic on the stock, with 36 rating the company as a strong buy or buy. While the total number of analysts that are bearish or neutral on the company is 20. This is important, because it shows how the majority of analysts are overly optimistic on the stock. As a result this could be an indication that the majority of successful investors have already purchased the company and may be in the process of taking their profits.
Moreover, the mainstream press is continuing to claim that Cisco is on the verge of taking advantage of new changes that are occurring in the way everyone is storing and retrieving information through cloud computing. This is when large amounts of data are stored on mainframe computers at remote locations versus having everyone place them in their devices. A good example of this can be seen in an article in Forbes:
Cisco Systems recently released a new cloud-based service, OnPlus, that helps its small-business partners provide network assessment, management and advisory services to their customers more easily. One of the major features of the new offering is that it allows value-added resellers (VARs) the ability to provide remote visibility of a customer’s network and attached devices. Cisco primarily competes with other network equipment and service providers like Juniper Network and Lucent Alcatel. We currently have a $21.21 price estimate for Cisco about 15% above the market price.
This is significant because it is showing how the mainstream press is taking the same kind of views as different analysts. Once this occurs, the odds increase that the company could be facing a number of different challenges when it comes to its earnings and future growth expectations.
This is the point that there could be some kind of negative surprise (which may cause the analysts to downgrade the stock) leading to a major reversal in prices. From a contrarian point of view, this is troubling as the current price is a reflection of these positive expectations. This increases the chances that the company could miss future earnings and revenue estimates.
Chambers Speaks Out
Despite the positive sentiment that is associated with the company, CEO John Chambers has said the firm is facing challenges associated with the culture inside the organization and the negative backlash from unsuccessful business ventures. Chambers commented that the firm is facing a number of issues going forward:
It is aspects of our operational execution that are not very strong . We have been slow to make decisions, we have had surprises where we should not, and we have lost the accountability that has been a hallmark of our ability to execute consistently for our customers and our shareholders. That is unacceptable. Today we face a simple truth: we have disappointed our investors and we have confused our employees. Bottom line, we have lost some of the credibility that is foundational to Cisco’s success – and we must earn it back. Our market is in transition, and our company is in transition. And the time is right to define this transition for ourselves and our industry. I understand this. It’s time for focus.
These comments are important, because they show Cisco is facing challenges from within. This means that the positive sentiments from analysts and the news media are nothing more than hype. Until the company is able to effectively focus on these issues. There will be continuing pressure on the stock. Over the course of time this means that earnings and revenues could come in below what many analyst are expecting. This raises the possibility for some kind of sell-off to occur.
Clearly Cisco Systems is facing a number of challenges when it comes to its operating environment and maintaining continuing growth. To be successful, the company will need to change from within, which will be time consuming and difficult. This means that the analysts’ estimates and positive news articles promoting the stock are ignoring these key factors. Once this occurs, the odds increase that Cisco could have some kind of negative earnings surprise.
Chassis, You Know Here:
A Chassis is a frame/housing for mounting the circuit components for Cisco Switches and Routers or any type of devices that provides power and a high-speed backplane. The frame also protects all of the vital internal equipment from dust, moisture, and tampering.
Making the Chassis to define even easier is;
A chassis is an enclosure; a container that holds things together... i.e. an egg carton holds eggs together inside. A chassis does the same thing; it holds the important things inside like wiring, power supplies etc.
General info of Backplane
Backplane is a circuit board with sockets that allows Supervisor engines Cards or modules to be inserted into these sockets and connect them to each other. Backplane is mounted on the Chassis.
Modules or line cards provide different types of interfaces, but the processing of packets is usually done in the Supervisor engine. Backplane is the medium for data flow between modules and Supervisor engines.
Additionally, most high-end switches off-load processing away from the supervisors, allowing line cards to switch traffic directly between ports on the same card without using any processing power or even touching the backplane. Naturally, this can't be done for all traffic, but basic layer-2 switching can usually be handled exclusively by the line card, and in many cases also more complex operations can be handled as well.
What is Line Card?
The line cards provide interfaces to the network.
A line card can terminate a line supporting voice POTS service, ISDN service, DSL service, or proprietary ones. Some line cards are capable of terminating more than one type of service.
Since an access network element is usually intended to interface many users (typically a few thousands) some exchanges have multiple line terminations per card. Similarly, it is common to have many line cards in the same network element.