1. A method, comprising: maintaining a plurality of routing topologies within a computer network, each of the routing topologies associated with a different corresponding delay; receiving a packet with an indicated delay budget at a particular node; updating the delay budget by subtracting an incurred delay up to and including the particular node since the indicated delay budget was last updated, wherein the incurred delay includes a queuing delay at the particular node between receiving the packet and forwarding the packet away from the particular node; selecting a particular routing topology of the plurality of routing topologies on which to forward the packet based on the updated delay budget and the corresponding routing topology delays; and forwarding the packet with the updated delay budget on the particular routing topology.