Emulex DCP_link manual Emulex X.25 User Facilities

X.25 Configuration 7-9

Two Way SVC, Number of LCNs - Determines the lowest LCN that can be used for two-way SVCs. This number must agree with your network subscription.

Outbound, Lowest LCN - Determines the lowest LCN that can be used for outgoing logical channels for SVCs. The value must be greater than or equal to the Lowest two-way SVC LCNs value plus the Number of two-way LCNs value.

Outbound, Number of LCNs - Determines the number of logical channels reserved for outbound-only SVCs. This number must agree with your network subscription.

Emulex X.25 User Facilities

The X.25 Recommendation addresses users' needs for versatility in their network requirements through a set of optional user facilities. These facilities give X.25 the capability of being tailored to meet varied network and user requirements and allow a network installer to fine-tune the network’s handling of such areas as security, accounting, routing, and performance. These facilities can be selectively and incrementally specified to the needs of the users on that network.

Many user facilities can be used within an X.25 connection to a PDN. Some of these facilities are read-only and may not be changed. User facilities available with Emulex X.25 include the following:

Flow Control Negotiation - If set to Yes, negotiates (downgrades) incoming calls containing either Window Size or Packet Size facility values that are greater than those specified. If set to No, rejects incoming calls containing either Window Size or Packet Size facility values that are greater than those specified. Negotiates, on a per-call basis.

Throughput Class Negotiation - Specifies, on a per-call basis, the throughput of data that can be transferred on a virtual circuit. The range is 75 bps to 64 Kbps.

Fast Select - If Yes, allows up to 128 bytes of user data to be included in Call Request packets. If No, user data is not included in Call Request packets Expands the Call and Clear user data fields from the normal 16 octets to 128 octets, enhancing the data field's usefulness for short- duration, low-volume, transaction-oriented applications. This facility is often used in the retail point-of-sale and credit card authorization terminal environment..