Download Broadmore 1700 - Force10 Networks

Configuration
E1 Nx64 SAM
Option
Definition
When to select
SRTS
(Synchronous
Residual Time
Stamp)
NOTE: SRTS is a proprietary timing algorithm and
may ONLY be used with specific written prior
permission from Carrier Access Corporation.
Additional license fees may apply.
With Unstructured
Service only
This method measures the Service Clock input frequency against
a network-wide ATM synchronization clock and sends the
difference signals in the AAL1 header to the destination
Broadmore 1700 circuit emulation interface. The different
signals are then combined with the network-wide ATM
synchronization clock to re-create the input service clock. If
more than one ATM clock synchronization is present in the
network, an alternate timing recovery method must be selected.
For this method to work, the ATM network must be
synchronized to a single network-wide clock source.
Table 7-22: DS1/E1 Nx64 CBR Service Type Options
Option
Definition
When to select
Unstructured
This option does not rely on a particular data
format. Bits received at the service interface
from the user equipment are packed into cells
without regard to framing. Boundaries for
channel and frame alignment are transparent
to the ATM service. A bit pattern (2.048 or
1.544 Mbps) sent in at one end is delivered
unchanged at the destination.
The entire bandwidth, including
framing bits, is assigned to one
Virtual Circuit (VC).
With this option, the ATM service interface
must be able to identify, group, and assign
each timeslot or group of timeslots a VC. The
service interface uses the framing bit to
detect channel boundaries. The selected
channels are packed into cells with an
additional control byte (a Structure Pointer)
added in some cells. The SP indicates to the
destination receiver the start of a block of
bytes that begins with the lowest channel
selected from the Channel Setup menu for a
particular PVC.
This ATM service emulates a pointto-point fractional T1/E1 circuit
without Channel Associated
Signaling (CAS)
Structured No CAS
Broadmore 1700 - Release 4.6
(Can be used for PCM 30 or PCM
31, and SDT is not required)
7-69