Summarizing WAN Connection Technologies

Table 22.3 summarizes the WAN connection technologies discussed in this chapter in order to
provide comparisons among them.

Summary of WAN Connection Technologies
Connection Max Throughput U.S. Availability Relative Cost
Asynchronous dial-up
56Kbps/DDS
56Kbps Widely available Low
Leased line T-1/E-1 1.544Mbps/
2.048Mbps
Widely available in
the U.S.
Medium
Leased line DS3 44.736Mbps/
34.368Mbps(E-3)
Widely available High
ATM 10Gbps. However, it
is virtually unlimited
from a protocol perspective.
Moderately available Very high
ISDN BRI 128Kbps for user,
16Kbps for control
data, and 48Kbps for
overhead
Moderately available Low. However, perminute
tariffs can
quickly alter this.
ISDN PRI 1.5Mbps T-1, and
about 2Mbps E-1
Moderately available Medium
DSL 128Kbps to 2Mbps
(some installations up
to 52Mbps)
Available in larger cities,
becoming more
available in rural areas
Low
Frame Relay Wide range of speeds,
from 56K over T-1 to
DS3 (45Mbps)
Widely available Low
Cable modem From 128 Kbps to
3Mbps
Widely available Low