DS3 Equivalent to 28 T1 Lines
DS3 service at a signaling rate of 44.736 Mbps is the equivalent
of 28 T1 lines at their signaling rate of 1.544 Mbps. Because
of the strict synchronization of TDM services, 28 T1 lines may
be multiplexed into a single DS3 service.
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 for Call Center Telephony
DS3 voice service can support up to 672 simultaneous telephone
conversations without blocking. If your call center or large corporate
PBX system requires this number of outside lines, DS3 is likely
far more cost effective than ordering the equivalent 28 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.
The Importance of DS0
DS0 and DS3 are part of the same set of digital signal standards.
DS0 is 64 Kbps, the bandwidth required to support one telephone
call of 8 bits at a sampling rate of 8 Kbps. DS3 has a speed
of 44,736 Kbps, commonly referred to as 45 Mbps. This speed level
was chosen so that 672 DS0s could be multiplexed into one DS3.
One DS3 can also multiplex 28 DS1 services. DS1 is the signal
level transmitted on a T1 line.