DS3 vs Multiple T1 Lines
Bonding T1 lines for greater bandwidth is a good value up to about
8x or 9x bonding. Above that, it makes better economic sense to
order DS3 service over fiber or T3 copper line. In metropolitan
areas with high levels of buildout, the decision point may be
less than 8 T1 lines.
When to Use Pseudowires
A pseudowire is a virtual "circuit" that emulates a
traditional digital telecom service but on a packet switched network.
MPLS networks are especially suitable for pseudowires. By using
a pseudowire circuit, you can get the point to point connectivity
you desire without having to re-engineer your facilities to accommodate
a different protocol network.
DS3 as an Internet Backbone
DS3 service configured as an dedicated Internet port offers 45
Mbps of upload and download bandwidth. This is ideal for small
and medium size ISPs and WISPs. that have exceeded the capacity
available from multiple T1 lines.
DS3 as Ethernet Transport
DS3 bandwidth at 45 Mbps can easily transport 10 Mbps Ethernet
over SONET or T3 line, even with the additional overhead needed
to convert from packet to TDM back to packet protocol. For Fast
Ethernet transport, an OC3 service at 155 Mbps would be required.
What is Fractional DS3 Service?
Fractional DS3, as the name implies, is a fraction of the full
DS3 bandwidth of 45 Mbps. Companies order fractional DS3 when
they don't need or want to pay for the full bandwidth offered
by DS3. Even with fractional DS3, you still need the full coaxial
or optical hardware support for 45 Mbps signaling. At low fractional
requirements, bonded T1 lines offer a more cost effective solution.