[[port-numbers]]
== Appendix A. Osmocom TCP/UDP Port Numbers

The Osmocom GSM system utilizes a variety of TCP/IP based protocols. The
table below provides a reference as to which port numbers are used by
which protocol / interface.

[[table.port]]
.TCP/UDP port numbers
[options="header",cols="10%,10%,40%,40%"]
|===============
|L4 Protocol|Port Number|Purpose|Software
|TCP|2775|SMPP (SMS interface for external programs)|osmo-nitb
|TCP|3002|A/bis/IP OML|osmo-bts, osmo-bsc, osmo-nitb
|TCP|3003|A-bis/IP RSL|osmo-bts, osmo-bsc, osmo-nitb
|TCP|4240|telnet (VTY)|osmo-pcu
|TCP|4241|telnet (VTY)|osmo-bts
|TCP|4242|telnet (VTY)|osmo-nitb, osmo-bsc
|TCP|4243|telnet (VTY)|osmo-bsc_mgcp
|TCP|4244|telnet (VTY)|osmo-bsc_nat
|TCP|4245|telnet (VTY)|osmo-sgsn
|TCP|4246|telnet (VTY)|osmo-gbproxy
|TCP|4249|Control Interface|osmo-nitb, osmo-bsc
|TCP|4250|Control Interface|osmo-bsc_nat
|TCP|5000|A/IP|osmo-bsc, osmo-bsc_nat
|UDP|2427|GSMTAP|osmo-pcu, osmo-bts
|UDP|23000|GPRS-NS over IP default port|osmo-pcu, osmo-sgsn, osmo-gbproxy
|===============