Communications network

A method of operating a communications network to convey Short Message Service (SMS) message data from first user equipment to second user equipment using the Internet Protocol (IP), wherein the communications network comprises an Evolved Packet Data Gateway (ePDG), wireless equipment, and a proxy server, the method comprising:

• with the wireless equipment, receiving a first SMS-over-IP message from the first user equipment over a first communications link having a first bandwidth;
• with the wireless equipment, routing the first SMS-over-IP message to the ePDG;
• and
• with the proxy server, while the first communications link is unavailable, receiving message data from the first user equipment over a second communications link having a second bandwidth that is less than the first bandwidth.

A non-transitory computer-readable storage medium storing one or more programs configured to be executed by at least one processor of user equipment having wireless circuitry and a display, the one or more programs including instructions for:

• receiving, using the wireless circuitry, a message from an Evolved Packet Data Gateway (ePDG) over a first communications link, wherein the message includes first message data and wherein the first communications link has a first bandwidth;
• receiving, using the wireless circuitry and while the first communications link is unavailable, a compressed message from the ePDG via a proxy server and a second communications link between the proxy server and the user equipment, wherein the second communications link has a second bandwidth that is less than the first bandwidth;
• and
• de-encapsulating the compressed message to retrieve second message data from the compressed message.