GTP Overview
GTP uses GTPv1-C, GTPv2-C and GTP-U on different types
of interfaces.
Enabling GTP security on Palo Alto Networks® firewalls
allows you to protect the mobile core network infrastructure from
malformed GTP packets, denial of service attacks, and out-of-state
GTP messages, and also allows you to protect mobile subscribers
from spoofed IP packets and overbilling attacks.
The firewall does not currently support GTP Security on S3
and S4 interfaces.
GTPv1-C is defined in 3GPP TS 29.060. It is used on a Gn interface,
that is, the interface between GPRS support nodes (GSNs) within
a public land mobile network (PLMN), and also across a Gp interface
between GSNs in different PLMNs. It is also used for roaming and
inter access mobility between Gn/Gp SGSNs and mobility management
entities (MMEs). GTPv1-C carries various types of control plane
signaling messages. The registered port number for GTPv1-C is 2123.
GTPv2-C is defined in 3GPP TS 29.274. It is used on various EPC
(Evolved Packet Core) signaling interfaces, such as S5, S8, and
S11. GTPv2-C carries various types of control plane signaling messages.
The registered port number for GTPv2-C is 2123.
GTP-U is defined in 3GPP TS 29.281. It encapsulates and routes user plane traffic across multiple
user plane interfaces such as S1, S5, S8, and N3 (for 5G). GTP-U messages are either
user plane or signaling messages. The registered port number for GTP-U is 2152.
NAT is not supported for GTP tunnel IP addresses with GTP stateful
inspection.
By default, PA-7000 Series firewalls with PA-7000-100G-NPC-A
and PA-7050-SMC-B or PA-7080-SMC-B perform tunnel acceleration to
improve performance and throughput for traffic going through GRE,
VXLAN, and GTP-U tunnels. Tunnel acceleration provides hardware
offloading to reduce the time it takes to perform flow lookups and
allows the tunnel traffic to be distributed more efficiently based
on the inner traffic. You can
Disable Tunnel Acceleration for ease of
troubleshooting.
