- What is an X.25 Network?
- X.25 Layers compared with TCP/IP
- X.25 Addresses (NUAs)
- Virtual Circuits
- X.25 Logical Channels - what are they?
- SVCs
- PVCs
- Data Transfer and Packetization - Differences from TCP
- X.25 Network Reliability
- IP over X.25
- XOT (X.25 over TCP/IP)
- Point to Point X.25
- DCE and DTE - what are they?
- The Physical Link
- LAPB - the data link layer
- LAPB - types of frame
- LAPB - frame structure
- X.25 Packet Layer - the network layer
- X.25 Packet Layer - packet types
- X.25 Facilities
- X.25 Resets
- Using the FarSync Sockets API to interface to X.25
X.25 Facilities
X.25 Facilities are generally used for communicating with the network, although many are also of end-to-end significance. Indeed, there is a class of facilities (X.25 Annex-G) reserved for end-to-end usage.
Facilities include such things as:
- Packet and Window size negotiation
- Throughput Class negotiation
- Reverse Charging
- Closed User Groups
- NUI selection
- Charging information
- Call deflection selection and redirection notification
Certain facilities are allowed in certain packet types - most can appear in Call Requests, but others, for example charging information, appear in Clear Indication packets and DCE Clear Confirmation packets.
14-Sep-2016