Medium and large fabric engineering rules

Overview

This section describes the functionality and limitations resulting from the use of the medium and large switch fabrics in high-speed circuit packs. Use this section to help plan the use of circuit packs in Main slots of the Alcatel-Lucent 1665 DMX shelf. Because of the smaller switch fabric in these circuit packs, they are less costly; however, the smaller switch fabric (12 STS-1) can not handle the same volume of cross-connections as the large switch fabric (48 STS-1). Therefore, circuit packs with medium-size switch fabrics have cross-connection restrictions.

Medium fabric circuit packs

The table below lists the Alcatel-Lucent 1665 DMX circuit packs equipped with medium switch fabrics.

Table 6-1: Circuit packs with medium switch fabrics

Circuit Pack	Apparatus Code	Slot(s)	Release	Comments
OC-12 OLIU(1 port)	LNW48	M1, M2	3.1	High-speed, Intermediate reach, 1310 nm, OSP hardened, 12 STS-1 VT fabric
	LNW50	M1, M2	3.1	High-speed, Long reach, 1310 nm, OSP hardened, 12 STS-1 VT fabric
	LNW54	M1, M2	5.1	High-speed, Long reach, 1550 nm, OSP hardened, 12 STS-1 VT fabric
	LNW203	M1, M2	9.0	High-speed, PTM-based, 12 STS-1 VT fabric

Large fabric circuit packs

The table below lists the Alcatel-Lucent 1665 DMX circuit packs equipped with large switch fabrics.

Table 6-2: Circuit packs with large switch fabric

Circuit Pack	Apparatus Code	Slot(s)	Release	Comments
OC-48 OLIU	LNW27	M1, M2	2.1	High-speed, long reach, 1310 nm, 48 STS-1 VT fabric
	LNW29	M1, M2	2.1	High-speed, extra long reach, 1550 nm, 48 STS-1 VT fabric
	LNW32	M1, M2	2.1	High-speed, long reach, 48 STS-1 VT fabric
	LNW76	M1, M2	2.1	High-speed, short reach, 1310 nm, 48 STS-1 VT fabric
	LNW202	M1, M2	7.1	High-speed, PTM-based, DWDM, 48 STS-1 VT fabric
OC-192 OLIU	LNW56	M1, M2	2.1	High-speed, intermediate reach, 1550 nm, OSP hardened, 48 STS-1 VT fabric
	LNW58	M1, M2	2.1	High-speed, short reach, 1330 nm, 48 STS-1 fabric
	LNW502	M1, M2	7.1	High-speed, PTM-based, DWDM, OSP hardened, 48 STS-1 VT fabric
Switch	LNW80	M1, M2	4.0	Switch Fabric Pack with no high-speed optical Interface.

Differences at the shelf level

This sections describes the impact of medium switch fabric circuit packs versus large switch fabric circuit packs at the shelf level.

Shelf with medium fabric main circuit packs

The following figure shows the Alcatel-Lucent 1665 DMX shelf with MAIN circuit packs containing 12 STS-1-VT switch fabric.

Figure 6-1: Alcatel-Lucent 1665 DMX with medium fabric Main circuit packs

A shelf equipped with medium switch fabric main circuit packs has the following capabilities:

Function Groups A, B, C, and D are general purpose slots and support all low-speed circuit packs. Some low-speed packs supported in Function Group slots also require the installation of VLF Main circuit packs in the shelf.
Function Group G is referred to as the growth slot. The growth slot supports only optical, low-speed circuit packs, these includes all of the OC-3/12/48/192 port cards as well as the LNW63, LNW73/73C, LNW74, LNW87, and LNW170 Ethernet cards. (Some low-speed packs supported in Growth slots also require the installation of VLF Main circuit packs in the shelf and are therefore not supported by the medium fabric main packs.)

When the LNW74 is installed in slot G1 or G2, only optical PTMs can be used.
Function groups A, B, and C have an STS add/drop capacity of 24 STS-1s. This is a hardware-based restriction imposed by the use of the medium-sized STS switch fabric in the MAIN cards.
Function Groups A, B, and C support up to 24 ported TMUX DS3 or EC1 ports.
Function Group D supports up to 48 ported TMUX DS3 or EC1 ports.
Function Group G does not support TMUX circuit packs.

Shelf with large fabric main circuit packs

The following figure shows the Alcatel-Lucent 1665 DMX shelf with MAIN circuit packs containing 48 STS-1-VT switch fabric.

Figure 6-2: Alcatel-Lucent 1665 DMX with large switch fabric Main circuit packs

A shelf equipped with large switch fabric main circuit packs has the following capabilities:

Function Groups A, B, C, and D are general purpose slots and support all low-speed circuit packs. (Some low-speed packs supported in these slots also require the installation of VLF Main circuit packs in the shelf.)
Function Group G is referred to as the growth slot. The growth slot supports optical, low-speed circuit packs. These include all of the OC-3/12/48 packs, the LNW705 and LNW785, as well as the LNW63, LNW73/73C, LNW74, LNW87, and LNW170 Ethernet. (Some low-speed packs supported in Growth slots also require the installation of VLF Main circuit packs in the shelf, and are therefore not supported by the large fabric main packs.) Growth slots can also house LNW20 TransMUX packs functioning in portless mode.

When the LNW74 is installed in slot G1 or G2, only optical PTMs can be used.
All function groups have an STS add/drop capacity of 48 STS-1s.
Function Groups A, B, C, and D support up to 48 ported TMUX DS3 or EC1 ports, 24 portless TMUX DS3 ports
Function Group G supports up to 24 portless TMUX DS3 ports

Engineering restrictions at the circuit pack level

This section describes engineering/cross-connection restrictions when using medium switch fabric circuit packs.

OC-12 medium fabric

The LNW48, LNW50, LNW54, and LNW203 employ a 12 STS-1/VT1.5 switch fabric with the following capacity:

784x784 VT matrix
216x216 STS matrix

Function Groups A, B, and C support 24 STS-1 add/drop capacity

Additional pass-through traffic is supported
Any circuit pack with a capacity of 48 STS-1s is limited to 24 STS-1s (ex. 24 DS-3 add/drop capacity with LNW19B)
1 virtual concatenation group (VCG) pair is accessible to GbE circuit packs

Function Groups D and G support 48 STS-1 add/drop capacity

Full add/drop capacity to circuit packs capable of 48 STS-1s

OC-48/192 large fabric

The LNW27, LNW29, LNW32, LNW56, LNW58, LNW76, LNW80, LNW202, and LNW502 circuit packs employ a large 48 STS-1/VT1.5 switch fabric with the following capacity:

2688x2688 VT matrix
432x432 STS matrix (for OC-48); 720x720 STS matrix (for OC-192)

Function Groups A, B, C, D, and G support 48 STS-1 add/drop capacity

Full add/drop capacity to circuit packs capable of 48 STS-1s
Two VCG pairs are accessible to GbE circuit packs

Source/destination engineering rules

Due to hardware limitations in medium switch fabric Mains, cross-connections may be denied even though the capacity of the cross-connect fabric has not been exceeded.

In addition to the position of the shelf, source/destination demarcation is also determined by the STS number. The lower STS number is the source and the higher STS number is the destination.

Source	<<<<<<<<<<<<<<<<	Destination
Main<<FNA<<FNB<<FNC<<FND<<FNG

Once a cross-connect utilizing a VT1.5 within an STS-1 is established, no part of that STS-1 can be used in a cross-connect to a slot/group on the other side of the shelf. For example, if a VT1.5 from an STS-1 entering the shelf at Function Group B1 (FNB1) was cross-connected to FNA1, another VT1.5 in that same STS-1 could not be cross connected to FNC, FND, or FNG.

Cross-connections made with the LNW7 circuit packs are exceptions to this rule. This pack is always the cross-connect destination. Hairpin cross-connections between these packs are not allowed.

Intra-port hairpins are supported by Alcatel-Lucent 1665 DMX. Yet when an Alcatel-Lucent 1665 DMX is equipped with medium fabric mains, intra-port hairpins are not allowed.