4.3.3 Packet routing and transfer functions

23.4013GPPGeneral Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) accessRelease 18TS

4.3.3.1 General

A route is an ordered list of nodes used for the transfer of packets within and between the PLMN(s). Each route consists of the originating node, zero or more relay nodes and the destination node. Routing is the process of determining and using, in accordance with a set of rules, the route for transmission of a message within and between the PLMN(s).

The EPS is an IP network and uses the standard routing and transport mechanisms of the underlying IP network.

The Maximum Transfer Unit (MTU) size considerations in clause 9.3 of TS 23.060 [7] are also applicable to EPS.

4.3.3.2 IP header compression function

The IP header compression function optimises use of radio capacity by IP header compression mechanisms.

When Control Plane CIoT EPS Optimisation is supported for PDN connections of IP PDN Type, if the IP header compression based on ROHC framework IETF RFC 5795 [77] is implemented in the MME and the UE, the ROHC profiles defined in TS 36.323 [78] may be supported.

4.3.3.3 Packet screening function

The packet screening function provides the network with the capability to check that the UE is using the exact IPv4-Address and/or IPv6-Prefix that was assigned to the UE.

4.3.3.4 IP Multicast Forwarding between a network accessed by LIPA and a UE

The Home eNodeB L-GW should support IP forwarding of packets to multicast groups between the UE and the network accessed by LIPA.