It is important to note that SDP is not suitable for the bulk transfer of data, as the size of UDP packets is limited. The current version of SDP does not incorporate a mechanism for packet fragmentation and reassembly. For this reason, it is desirable that the results of a nameserver lookup be communicated by some other out-of-bound mechanism - such as the responding nameserver supplying the URL of the URC for the resource in question, rather than the URC itself.
If this is assumed, the format of the URC is not particularly relevant as far as the use of SDP is concerned.