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SBSLITE Telecom Standard Product Data Sheet
Preliminary
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010883, Issue 2
35
Table 1 Structure for Carrying Multiplexed Links
SBI Column
1
6
7
8
15
16
17
18
19
268
269 270
Row
1
2
-
-
C1
-
-
SPE1 SPE2 SPE3 SPE1
SPE1 SPE2 SPE3 SPE1
SPE1 SPE2 SPE3
-
-
-
-
-
SPE1 SPE2 SPE3
9
-
-
-
-
-
SPE1 SPE2 SPE3 SPE1
SPE1 SPE2 SPE3
1
SPE Column
2
3
3
5
6
6
6
7
90
90
90
The mappings for each link type are rigidly defined, however the mix of links transported across
the bus at any one time is flexible. Each SPE, comprising 85 columns numbered 6 through 90,
operates independently allowing a mix of T1s, E1s, TVT1.5s, TVT2s, DS3s, E3s or Fractional
links. For example, SPE1 could transport a single DS3, SPE2 could transport a single E3 and
SPE3 could transport either 28 T1s or 21 E1s. Each SPE is restricted to carrying a single tributary
type. SBI columns 16-18 are unused for T1, E1, TVT1.5 and TVT2 tributaries.
Tributary Numbering
Tributary numbering for T1 and E1 uses the SPE number, followed by the tributary number
within that SPE and are numbered sequentially. Table 2 and Table 3 show the T1 and E1 column
numbering and relates the tributary number to the SPE column numbers and overall SBI column
structure. Numbering for DS3 or E3 follows the same naming convention even though there is
only one DS3 or E3 per SPE. TVT1.5s and TVT2s follow the same numbering conventions as T1
and E1 tributaries respectively. SBI columns 16-18 are unused for T1, E1, TVT1.5 and TVT2
tributaries.
Table 2 T1/TVT1.5 Tributary Column Numbering
T1#
SPE1 Column
SPE2 Column
SPE3 Column
SBI Column
1,1
2,1
3,1
1,2
2,2
1,28
2,28
3,28
7,35,63
19,103,187
20,104,188
21,105,189
22,106,190
23,107,191
7,35,63
7,35,63
8,36,64
8,36,64
34,62,90
100,184,268
101,185,269
102,186,270
34,62,90
34,62,90