NANC 183

PDU Size

Origination Date :01/05/1998

Originator:NANC T&O

Description:

Maximum and currently supported PDU sizes needs to be reviewed by the NANC T&O team to insure that large PDU’s that can be created today will not cause problems in either NPAC SMS, LSMS, or SOA systems. If PDU size is an issue it should be documented in the IIS.

Final Resolution:

Linked to NANC 184 and ILL 79.

It was noted that RFC1006 in one vendor’s implementation support a minimum size of 128 bytes and a maximum of 65,536 bytes. The factory default in the case of this product is 2048 bytes.

Feedback to date has indicated that most CMIP products have no limits. However, the OSI stacks have limits ranging from 10K to 64K. Limits can be at presentation and transport layers. HP has been called for questions as to which layer of the protocol stack that size becomes an issue transport or presentation. It has been indicated that there is no limit in the Marben products at any layer of the stack.

The PDU sizes have been provided reviewed. Updates are being made to the PDU sizing matrix to reflect future change orders ILL 79 and NANC 179 as well as overhead bytes. Right now the recovery requests and the LSMS create results notifications are the items that are of concern. These network data download may not be as large of a concern due to the fact that large amounts of network data would not be entered in 1.0 that would cause a large PDU. For SV recovery smaller recovery time windows could be used to reduce the size of the data returned. We need to consider if we need linked replies in the future for these messages that could be an issue.

NANC 186 and 187 are being updated to reflect the outcome of the analysis done for this change order. This change order is closed no action.

Related Release:

N/A

Status: Closed