cisco 1720 router advice

EJizzel

Im in dire need of advise!! I noticed a 1720 router on sale on the internet and wanted to know if that is sufficient for the CCNA. I recently started studying for the CCENT and only touched a simulator a hand full of times but I want some real equipment.

Below is a a show version and specs for the router.

The Cisco 1720 Router provides 1 Fast Ethernet port & 2 integrated WIC slots.
Loaded with 49MB RAM & 8MB Flash memory configuration with IOS 12.3(9) Edition

Show Version Screen Capture:
Router>sh ver
Cisco Internetwork Operating System Software
IOS (tm) C1700 Software (C1700-SY7-M), Version 12.3(9), RELEASE SOFTWARE (fc2)
Copyright (c) 1986-2004 by cisco Systems, Inc.
Compiled Fri 14-May-04 15:39 by dchih
Image text-base: 0x80008120, data-base: 0x80DDF300

ROM: System Bootstrap, Version 12.0(3)T, RELEASE SOFTWARE (fc1)

Router uptime is 2 minutes
System returned to ROM by power-on
System image file is "flash:c1700-sy7-mz.123-9.bin"

cisco 1720 (MPC860T) processor (revision 0x501) with 36864K/12288K bytes of memory.
Processor board ID JAD043300NO (1956758410), with hardware revision 0000
MPC860T processor: part number 0, mask 32
Bridging software.
X.25 software, Version 3.0.0.
1 FastEthernet/IEEE 802.3 interface(s)
32K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102

This will be my first cisco purchase, any help is greatly appreciated.

Netstudent

The router is fine, but I'm not sure about that image. You may want to check the feature navigator. At any rate, images are easy to get, so that shouldn;t be a deciding factor. Looks like 8MB of flash so you may see if that can be upgraded or think about booting from a tftp server. I think some of the better images will require 16Mb of flash.

mikej412

Just remember the 1720 doesn't do trunking -- so no router on a stick.

Netstudent wrote:

images are easy to get

Ahem

Easy to get with a valid SmartNet Support Contract.

kafifi13

I wouldn't get this. See if you can get a 2610 for cheap.

Netstudent

mikej412 wrote:

Just remember the 1720 doesn't do trunking -- so no router on a stick.

Netstudent wrote:

images are easy to get

Ahem

Easy to get with a valid SmartNet Support Contract.

Ya thats what I meant.

But you will need more than one router, and as others said, you may want to get another router than can sub out an ethernet interface with dot1Q.

EJizzel

im interested in this router because its only $50, i been looking and that looks like a good deal for a 1700 series router. I hate to sound

I hate to sound like a complete idiot but can someone explain Router on a Stick in lamens terms. LOL. Im still very new to this.

mikej412 wrote:

Just remember the 1720 doesn't do trunking -- so no router on a stick.

Netstudent wrote:

images are easy to get

Ahem

Easy to get with a valid SmartNet Support Contract.

Netstudent

Router on a stick basically means you are using a single layer 3 device such as a router to route between multiple IP subnets or multiple VLANS within a switched environment.

See if you were to put two machines on the same switch and gave them both static IP addresses from 2 different subnets, they would not be able to establish IP connectivity. BUT, if you can put a tag on those frames, and give them a trunked path to a layer 3 device, then that layer3 device can facilitate the communication between those two machines.

The router's ethernet interface connects to the switch, and that cable is the "stick" in the analogy. The ethernet interface is logically divided between multiple subnets by using subinterfaces and definfing a VLAN tag to be encapsulated to the frame. The encapsulation methods are 802.1Q and ISL. The VLans separate broadcast domains, because broadcasts can only be propagated within the vlan it originates.

Subinterfaces save money and vlans save bandwidth while increasing scalability.

A trunk by definition is any link where multiple VLANS can traverse. Each frame(except the native vlan frame) is encapsulated with a vlan tag for identification. So by creating logical subinterfaces/subnets on a router's single port you are creating a trunk because multiple vlans will traverse that link.

HTH, my nizzel!

mikej412

EJizzel wrote:

lamens terms. LOL.

Probably not Hopefully you followed Netstudent's post -- It's something you eventually learn studying for the CCNA, if we don't scare you away first.

For a home lab you'd do this on a Router that has a Fast Ethernet interface available, but there are 2 exceptions. The 1720 won't do it. And a 2610 Router with a 12.2T or higher IOS version can do it on it's 10 Megabit interface.

Netstudent

Sorry, I guess I don't do lamens terms that well. hmmm

EJizzel

Thanks Netstudent, I THINK I got the understanding of "Router On a Stick" (that just kills me)
I think I'm going to pass on this one, router trunking definitely seems like something that is VERY important to know. I checked out ebay for some 2610 and they seem to be of a decent price.

Thanks to everyone for the help.