Draft by NA/AR&RSC

Proposed Amendments to cater for DWA (ARR#19)

Approved at MC#31

Usage of High Level Interface (HLI)

(Revised after MC#31) Version 5.0

Background/Objective

1.1In SMW3 2nd & 3rd 10G Upgrades, some stations are equipped with HLI at STM-4, STM-16 and STM-64. In SMW3 4th 10G Upgrade, 6 stations (namely Mersing, Penang, Satun, Jeddah, Yeroskipos and Tetuan) are equipped with both STM1 interfaces and HLI and the other 33 stations are equipped only with HLI (i.e. no STM1 interface).

1.2After the 4th 10G Upgrade, 62% of interfaces (17,028 STM-1 equivalents) in the SMW3 system are HLI compared to 38% of interfaces (10,288STM1 equivalents) are STM-1 interfaces.

1.3As HLI will be more prevalent after the 4th 10G Upgrade, the restriction on the use of HLI for STM-1 traffic is no longer seen to be necessary.

1.4This paper proposes principles for allocation and use of HLI to be applied by the NA.

1.5After the 5th Upgrade, DWA access via the SLTE will be allowed. As this will be via the SLTE not the SIE, the reduced activation threshold for SIE will not apply since all the timeslots across the system will be utilized.

Principle

2.1Below principles on the usage of HLI, which are extensions of existing rules (IP5/SC3) governing VC4 routing between Segment-S and Segment-T equipment.

2.2In order to optimize the utilization of SIE at all Terminal Stations and the amount of connections to the backhaul or other terrestrial/submarine networks, the following principles shall apply.

a)By default new VC4 traffic will be assigned on a STM1 interface where it is available. If not, the new VC4 traffic will be assigned on a HLI.

b)For a new concatenated traffic the most appropriate High level interface will be used by default e.g. VC4-4c will be assigned on a STM4 interface and likewise VC4-16c will be assigned on a STM16 interface. However VC4-4c may be assigned on STM16 interface if STM4 is not available, and likewise for VC4-4c and VC4-16c in STM64 interface.DWA traffic will only be allowed on the SLTE interfaces.

c)However to ensure the optimal use of HLI, traffic will be allowed to be terminated in HLI with the following activation thresholds.

Party who is activating 3 or 4 VC4 in the same request may have a dedicated STM4 port
Party who is activating between 12 and 16 VC4 equivalent in the same request may have a dedicated STM16 port
Party who is activating between 48 and 64 VC4 equivalent in the same request may have a dedicated STM64 port
Party who is activating DWA will have to assign 64 VC4 equivalent in the same request and will have dedicated SLTE ports

d)A new HLI will be assigned between Segment S and Segment T when the existing one is fully filled or becomes insufficient to accommodate additional concatenated requirement.

e)A third party or non-SMW3 Terminal Party is not allowed to access directly to HLI or any other Segment-S equipment.

f)There are STM1’s/STM4’s/STM16’s dropped at HLI’s currently before the establishment of HLI Usage principles. These circuits will be left as they are in order to avoid unnecessary circuit interruptions. However, re-grooming may be arranged if these circuits affect activation of concatenated circuits. If any re-grooming was to be carried out,such re-grooming shall be done to the next available lower level of HLI port. For example, if STM-16s are terminated in STM-64 HLI port and need to be re-groomed, these STM-16s will be re-groomed to next lower level of STM-16 HLI ports. However, if the lower level of HLI is not available to meet the requirement of existing concatenated traffic, it will not be re-groomed to lower level of HLI. For example, if 3 STM-16s (concatenated) are terminated in STM-64 HLI port and need to be re-groomed toget a free STM-64 HLI port, these STM-16s will to be re-groomed to STM-16 HLI ports. However, if STM-16 HLI ports are not available, there will be no re-grooming as further re-grooming for this circuit in STM-4/STM-1 ports is not technically possible.

g)A HLI Pool has been established to cater for shortage of HLISIE ports. When depleted, HLI Pool will be replenished by using the relevant fund approved by MC. The detailed procedure is given in the document “Management of HLI Pool & Shipmentof Cards”.This does not apply to DWA ports which are assigned on the SLTE.

2.3Notwithstanding paragraph 2.2 ( a, b, c )above, there shall be no restriction on the usage of HLI in Terminal Stations where their Segment T is equipped or become equipped with the appropriate cross-connect capabilities andsame isused to activate /groom/demux/switch the new traffic. In such Terminal Stations, HLI can be used to activate new Lower Order Traffic without restriction. However, the condition of assigning new HLI as defined in paragraph 2.2(d) shall continue to apply.

Action Points Required by Terminal Stations

Cross-Connect Capabilities

Terminal Parties are to update the AR&RSC/NA as and when there are any changes on the following items:-

The current and the planned cross-connect capabilities of their Segment T equipment.

The charge for grooming/demux/switch of traffic using Segment T equipment payable by the requesting party to the terminal party where applicable.

A form is already sent to all the terminal stations for fill their correspondence details .A copy of form is attached here also for reference.