### Description
Please check attached pcap. [siptrace.pcap.gz](https://github.com/kamailio/kamailio/files/3688791/siptrace.pcap.gz)
Kamailio send INVITE (packet 1) from port `TCP/42394`. SIP trace encapsulate INVITE (packet 2) and encodes Kamailio source port `TCP/5060`
#### Debugging Data HEP header parsed by lua [disector](https://github.com/sipcapture/hep-wireshark) ``` HEP3 Protocol HEP ID: HEP3 Length (Bytes): 1574 Protocol family: IPv4 Protocol ID: TCP Source IPv4 address: 172.21.0.131 Destination IPv4 address: 192.168.57.11 Source port: 5060 Destination port: 5060 Timestamp: 1570150645 Timestamp us: 740165 Protocol Type: SIP Capture ID: 1 Payload [truncated]: INVITE sip:911@192.168.57.11;transport=tcp SIP/2.0\r\nRecord-Route: sip:172.21.0.131;transport=tcp;lr=on;ftag=KvNj7jXrmK89p\r\nVia: SIP/2.0/TCP 172.21.0.131;branch=z9hG4bK7c2d.2d8104273b7063309f5694ac963c9ad8.0;i=21 ``` [HEP format description located here](https://github.com/sipcapture/HEP/blob/master/docs/HEP3_Network_Protocol_Spe...).
### Additional Information
* **Kamailio Version** - output of `kamailio -v`
``` / # kamailio -v version: kamailio 5.1.6 (x86_64/linux) flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144 MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: unknown compiled on 11:01:40 Oct 4 2018 with gcc 6.4.0 ```
* **Operating System**: Docker container Userland ``` / # cat /etc/os-release NAME="Alpine Linux" ID=alpine VERSION_ID=3.8.1 PRETTY_NAME="Alpine Linux v3.8" HOME_URL="http://alpinelinux.org" BUG_REPORT_URL="http://bugs.alpinelinux.org" ``` Kernel Amazon Linux 2 ``` / # uname -a Linux proxy-dc0-0 4.14.128-112.105.amzn2.x86_64 #1 SMP Wed Jun 19 16:53:40 UTC 2019 x86_64 Linux ```