Demystifying the WAN
Sangoma’s WAN EduKit puts experience in your hands.
- By James Carrion
- February 01, 2003
Many of you may feel comfortable supporting and troubleshooting local
area networks (LANs) but cringe when it comes time to support wide area
networks (WANs). Because Ethernet is such a ubiquitous LAN technology,
most network admins understand the lingo of hubs, switches, NICs, 10BaseT
and so on; but throw around terms such as CSU/DSU, DTE, DCE, CIR, X.25
and the average network admin, short of those who are CCNA-certified,
look as though you were speaking K-PAXian. Although the Sangoma WAN EduKit
isn’t a primer on learning WAN basics, it provides lab hardware that will
help you get hands-on experience while you’re learning how to set up and
troubleshoot X.25 or frame relay-based WANs.
Sangoma Technologies makes an interesting line of products that combines,
into one card, all the physical layer technology you need to get a WAN
connection up and running and turn your PC into a WAN router. Normally,
to set up an X.25 or frame relay-based WAN requires purchasing components
such as a CSU/DSU, a router with a serial interface and cables to connect
them together. With the all-in-one card, simply install it in a PC, and
the operating system sees it as another network card to which it can route
packets that can then be transmitted by the integrated CSU/DSU out to
the frame relay or X.25 network.
The EduKit comes with an S5142 card with a secondary mounting clip, one
V.35 back-to-back cable, and drivers for Windows 98 and Windows 2000.
There’s also support for Linux, FreeBSD and OpenBSD but you’ll have to
download those drivers from ftp.sabgoma.com/pub. Install the card in an
available PCI slot; install the secondary mounting clip, which is attached
to the S5142 card by a ribbon cable; and plug the V.35 cable between the
card and the mounting clip to create a pseudo loopback testing environment.
At this point, you’re simulating a Data Terminal Equipment (DTE) connection
to a CSU/DSU, which, in turn, is serial-connected to a Data Circuit-Terminating
Equipment (DCE) via the loopback connection to the card itself.
When you run the software, you can choose to configure and test an X.25
or frame-relay connection. If you choose frame relay, two windows open:
one for the DCE (called the Customer Premises Equipment or CPE) and one
for the DTE (called the Access Node). You can then configure the pertinent
parameters—like DLCIs, signaling, transmission rate and so on—to create
a frame relay permanent virtual connection (PVC).
When running the X.25 labs, two windows also pop up, one for the DTE
and one for the DCE. You have the same configuration and troubleshooting
abilities, including being able to run a line trace. Although the interface
may be straightforward to the WAN expert, online help is nonexistent so
you’ll have to rely on reading the online lab manuals to familiarize yourself
with running lab tests.
You’ll need a good solid background in WAN theory in order to understand
and maximize the use of this kit. If you’re a WAN newbie, you may want
to check out the excellent free WAN educational materials available on
the Internet, for example, at www.marconi.com/html/education/webbasedwantheory.htm.
Getting a grasp of WAN concepts is no easy task—especially if you don’t
have the opportunity to perform hands-on configuration at your workplace.
Sangoma offers a unique product that will help you reinforce the WAN theory
you’ve learned in the classroom environment. Put the lab exercises through
the paces and soon you’ll be spouting off WAN terminology that will make
others notice your technical prowess.
WAN EduKit, $549 for U.S.-certified educational institutions, $849
for all others; Sangoma Technologies, (905) 474-1990, www.sangoma.com.
James Carrion, MCM R2 Directory, MCITP, MCSE, MCT, CCNA, CISSP has worked as a computer consultant and technical instructor for the past 16 years. He’s the owner of and principal instructor for MountainView Systems, LLC, which specializes in accelerated Microsoft Certification training.