Log in to the system using PCPro, and perform a download. Go to the top and select communications, then feature activation. This will show you what you are licensed for. If you have netlink licenses then you are probably connected through netlink. After you log in the system will show you the firmware level on the bottom.
If 84-26 has one IP address, then you are programmed for 16 DSP's (depending on software and hardware levels. Older software and hardware required one IP address per 16 DSP's, plus one address for the IPLA card. Newer software/hardware required one IP address for the card and only one for all possible DSP's regardless of the size of the IPLA card. If you have older stuff and a 32 IPLA card then you need 3 IP addresses. One for the card and 2 for the 32 DSP's in 84-26. If you have a 32 IPLA with only one IP address in 84-26, then the system could be accessing a port without an IP address, thus resulting in one way speech.