Routers, Cisco IOS Software, and Memory Requirements for Labs

Throughout this book, every lab has different hardware and software requirements. As mentioned earlier, preceding each lab is a section entitled "Equipment Needed." This section lists the minimum amount of equipment needed to complete that lab. Some labs are rather easy and might require only two or three routers with IP routing software. Other labs, such as those for configuring SNA, are rather complex and require the enterprise feature set and multiple routers. Finding routers, hubs, and such can be difficult.

Unfortunately, it is hard for some companies to realize the benefit of the age-old saying "Practice makes perfect." Companies can have a hard time finding enough room in the budget for labs so that their engineers can finely hone their skills.

Personally understanding the difficulty in attaining networking equipment, I have tried to involve the fewest amounts of routers/hubs as possible in these labs. I've also made the studies independent of one another, so if you don't have access to a Token Ring/Ethernet router or a switch, you can still perform a majority of the labs. For example, to perform the translational bridging lab, you need a Token Ring interface and an Ethernet interface on the same physical router. Because many Cisco routers can accommodate multiple LAN segments of different types, I won't go into details on specific router models. A good rule to follow when investing in new routers is, the more modular the router is, the more flexibility you have in creating multiple models. Investing in modular routers also protects your investment because most routers can be upgraded with the installation of new networking modules.

NOTE

The Comdisco lab uses primarily Cisco Catalyst 5500s, Cisco 2500s, 4500s, and 3600 series routers for modeling network scenarios. The Cisco 3600 series router can accommodate almost any networking requirement; this includes ATM, Gigabyte Ethernet, Voice over IP or Frame Relay, along with VPN technology.

When all the hardware is gathered, you are ready to begin discussing the Cisco Internetwork Operating System (IOS) Software releases, DRAM memory, and FLASH memory requirements that the models require. All three are tightly related to each other. The protocols and Cisco feature sets that you use drive the amount of DRAM memory needed to execute that feature. The Cisco IOS feature set is stored in FLASH memory. Therefore, the more features and protocols that are in use, the more DRAM and FLASH memory will be required. The labs listed in this book utilize most of the major routing protocols and most major feature sets. To easily accommodate this, the Enterprise Plus feature set could be installed on all the routers. The Cisco IOS Software release level should be at least 11.2. x or 12.0. x. If you are specifically practicing for the CCIE Lab Exam, use a minimum IOS level of 12.0 on all routers. If the lab requires an IOS feature greater than IP routing, it will be noted as a requirement.

NOTE

To find the exact minimum memory requirements for the specific Cisco IOS Software and feature set in use, consult Cisco's Web page, www.cisco.com.