Which is a protocol used in the traversing of media across a firewall through the Expressway?

Which is a protocol used in the traversing of media across a firewall through the Expressway?
B . 460 18/19
D . 239
F . 245
G . SIP

Answer: D

Explanation:

Traversing firewalls

C Administration

C SIP calls

C H.323 calls

https://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/expressway/config_guide/X8-1/Cisco-Expressway-IP-Port-Usage-for-Firewall-Traversal-Deployment_Guide-X8-1.pdf