I made the suggested changes, but still have issues. I thought specifying "transport=tcp" in the peer definition section would make Asterisk use TCP. Despite the changes specified, SIP still uses UDP (verified with the Wireshark pcap tool). I have noticed, however that Asterisk is in fact listening for tcp traffic on port 5060.
I have two Asterisk instances running on two separate servers on a local network. One Cisco IP phone is connected to each Asterisk instance. The two Cisco IP Phones are using Skinny. The Asterisk instances talk to each other using SIP, instead of IAX. I need this particular setup as I am running a software that analyzes the TCP packets.