Information Technology Reference
In-Depth Information
Note:
When you are seeking a WAN service, the options can vary depending service
provider offering, so it is recommended to review options from multiple WAN service
providers.
Figure 6-2 illustrates the use of modules, or blocks, in the enterprise edge.
Enterprise Campus
Enterprise Edge
Internet/WAN
Building Access
DMZ/E-Commerce
ISP 1
Building Distribution
Internet
ISP 2
Campus Core
Remote Access VPN
PSTN
WAN/MAN
Data Center/Server Farm
Frame/TDM/
ATM/MPLS
Figure 6-2
WA N I n t e r c o n n e c t i o n s
Several factors should be considered when selecting a WAN transport technology. Some
WA N o p t i o n s a r e p u b l i c I n t e r n e t b a s e d , a n d s o m e a r e p r i v a t e WA N b a s e d . G e o g r a p h y
also plays a key role in what WAN technologies are available in a given area. Major cities
have the most WAN transport options, and rural areas are more limited as to the availabil-
ity of WAN service options.
Ta ble 6 - 2 examines some WAN technologies and highlights some common factors used to
make WAN technology selections. This information also reflects the different characteris-
tics of each WAN technology. However, keep in mind that your service provider offerings
limit the WAN technology choices available to you during your selection.
