From cb782b99ff51fe55f397d7cdcb9a442ea1485e4c Mon Sep 17 00:00:00 2001 From: Stefan Sperling Date: Tue, 3 Apr 2018 16:03:15 +0200 Subject: document the purpose of IP addresses used by GGSN tests The purpose of the various IP addresses used by our GGSN tests is not immediately clear. Add documentation based on the current status quo. Change-Id: I079efcff3dab09d71330625f5b661cd81e42bf38 --- ggsn_tests/GGSN_Tests.ttcn | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'ggsn_tests/GGSN_Tests.ttcn') diff --git a/ggsn_tests/GGSN_Tests.ttcn b/ggsn_tests/GGSN_Tests.ttcn index 2b7de969..14690628 100644 --- a/ggsn_tests/GGSN_Tests.ttcn +++ b/ggsn_tests/GGSN_Tests.ttcn @@ -20,16 +20,35 @@ module GGSN_Tests { const integer GTP1U_PORT := 2152; modulepar { + /* Default IP addresses. May be overridden by GGSN_Tests configuration files. */ + + /* The SGSN simulated by TTCN3 will bind to these addresses for GTP control and GTP user planes. */ charstring m_bind_ip_gtpc := "127.23.42.1"; charstring m_bind_ip_gtpu := "127.23.42.1"; + /* Addresses the GGSN which is being tested is listening on for SGSN connections. */ charstring m_ggsn_ip_gtpc := "127.0.0.6"; charstring m_ggsn_ip_gtpu := "127.0.0.6"; + /* + * Our tests expect to see these DNS servers in 'Create PDP context responses' sent by the GGSN. + * These addresses must therefore match 'ip[v6] dns' options configured in osmo-ggsn.conf. + * + * These addresses are not expected to serve actual DNS requests. However, tests may expect to be + * able to ping these addresses (currently, IPv4 addresses must respond with an ICMP 'echo reply', + * and IPv6 addresses may respond with either ICMPv6 'echo reply' or 'destination unreachable'). + */ charstring m_ggsn_ip4_dns1 := "192.168.100.1" charstring m_ggsn_ip4_dns2 := "8.8.8.8" charstring m_ggsn_ip6_dns1 := "2001:4860:4860::8888" charstring m_ggsn_ip6_dns2 := "2001:4860:4860::8844" + + /* + * Additional address ranges are defined in osmo-ggsn.conf from which addresses are assigned + * to MS "behind" the simulated SGSN. These addresses appear on tun devices used by osmo-ggsn. + * The tests expect to be able to send ping packets between any two simulated MS within the same + * address range. This requires IP forwarding to be enabled on the corresponding tun interfaces. + */ } type set PdpContext { -- cgit v1.2.3