With Cisco's router lineup changing so frequently, it can be difficult to stay up to date. What are the current models of routers, and which router would you use for which situations?
What's missing from the lineup?
For those of us who have been working with Cisco routers for some time, some of the most well-known routers are missing from the current lineup. Cisco discontinued the 2600 and 3600 Series routers some time ago. For the remote branch office and SMB market, these routers were always the workhorse of the Cisco router lineup.
In my opinion, it wasn't their capabilities that made them obsolete. They could do just about anything that the latest routers could do. For that reason, many shops are still using them.
What made these series of routers depreciate was the limitation of their CPU processing, Flash, and RAM storage. The Cisco IOS grew to be larger than what those routers could handle efficiently with the maximum amount of RAM.
In addition, the packet load of the typical network grew so much that Gig-Ethernet became common on networks. These routers just didn't have the processing to handle that throughput with the CPU that they had.
Meet the ISRsWhat's really been new in the last year or so is the concept of Cisco's Integrated Services Routers (ISR). As you can see in Figure A, the ISR is what Cisco calls all but its larger "services aggregation platforms."
ISRs work for all companies — from the single telecommuter at the home office to the medium or large company running full BGP to the Internet. Cisco dubbed these routers "integrated services" because not only do they route like a traditional router, but they can also provides other services such as IPSec VPN, firewall, intrusion prevention, and VoIP call management.
Which router do I need?People often ask me which router they should use for a specific situation. To begin, I think Figure A does a decent job of illustrating Cisco's available routers and the load they can take (as illustrated by the light blue column in the graphic).
Of course, there's no hard and fast rule telling us which router to use for which situation. However, here are some general guidelines that I suggest using.
Home office or small branch office
Let's say you have a home office worker who needs more than just a periodic VPN connection. The employee will be working a full 40-hour workweek over a site-to-site VPN, and you want him or her to have the most reliable and best performing connection possible.
Cisco 800 Series routers are ideal in this situation. They're great performing routers for a single person or even a small office of up to 10 people. They have the full Cisco IOS, including the latest IOS 12.4 including features such as Firewall, IPS, VPN, VLAN, QoS, NAC, and even high availability features. There are different models for different applications, including ISDN, DSL, and routers with integrated wireless.
I use a Cisco 871W router at my house. In addition to it being a great router to connect to the Internet, it's an excellent router for testing Cisco IOS commands. I also recommend the 800 Series routers to CCNA and CCNP candidates as the best option for studying IOS commands.
Remote office of 25 workers
For remote offices that have 25 or so workers, Cisco 1800 Series routers are an excellent choice. This router is perfect if all you need is a router to connect your office to the Internet, VPN, firewall, and wireless.
Remote office of 50 workers
If you're looking for the same basic functionality of the 1800 Series but need a lot more performance and expandability, Cisco 2800 Series routers are what you need. With the 2800 series lineup, you can get everything that's in the 1800 Series plus redundant power supply options, Gig-Ethernet ports, Network Module (NM) expansion slots, VoIP Call Manager Express (CME) with SRST, and much more performance.
Having the NM card slot lets you add things such as a 36-port switch with PoE, a DS3 ATM, a 24-port VoIP module, an intrusion detection module, a network analysis module, or a Cisco Unity Express voice mail module. In my opinion, the Network Module slot on the 2800 Series is where the Cisco router lineup really starts to get exciting.
Remote or HQ office of 100 workers
Cisco 3800 Series routers are similar to the 2800 Series in that there are a lot of HWIC and NM options for them. But what sets them apart from the 2800 Series is the sheer performance of the hardware and the number of HWIC and NM card that you can put into them.
Campus or large HQ office
For very large campus or service providers, the Catalyst 6500 and 7200/7300 Series platforms are for you. Cisco calls these "service aggregation platforms." These are very high-performance networking platforms with a huge capacity for expansion.
A quick disclaimer: Always read the specifications for the router you're considering, and consult with your local SE or experienced Cisco reseller to make sure you get the best router for the job.
It can be difficult to stay up to date with Cisco's ever-expanding and changing router offerings. In this article, I covered the different scenarios where you would need a Cisco router and the five major Cisco router platforms that fit into those scenarios. I hope that the next time you need to select a Cisco router, you know exactly which router line to turn to.
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