Abstract: The following description is directed to managing a hierarchical network including one or more network zones. In one example, a method of managing a hierarchical network includes collecting network state from respective devices of a network zone; using the collected network state to build an aggregated topology of the network zone; and transmitting the aggregated topology of the network zone to a traffic engineering service.

Abstract: Network packet tracing may be implemented on packet processors or other devices that perform packet processing. As network packets are received, a determination may be made as to whether tracing is enabled for the network packets. For those network packets with tracing enabled, trace information may be generated and the network packets modified to include the trace information such that forwarding decisions for the network packets ignore the trace information. Trace information indicate a packet processor as a location in a route traversed by the network packets and may include ingress and egress timestamps. Forwarding decisions may then be made and the network packets sent according to the forwarding decisions. Tracing may be enabled or disabled by packet processors for individual network packets. Trace information may also be truncated at a packet processor.

Abstract: Techniques for dynamic augmentation of server rack network capacity are provided herein. Network nodes are described that are connected between server rack switches and a rack aggregation layer device. A port allocation controller is also described that can automatically reconfigure the network nodes to create connections, via the network nodes, between the rack aggregation layer device and the server rack switches. These network node connections can be used to alter the network capacities of the server rack switches in response to changing network demands.

Abstract: The following description is directed to configuring network devices. In one example, at a network device deployment pipeline, a request can be received from a non-integrated configuration tool to configure a network device of a network. The configuration of the network device can be scheduled so that both an integrated configuration tool of the network device deployment pipeline and the non-integrated configuration tool can configure the network.

Abstract: A method for adjusting capacity in a multi-stage routing network includes monitoring a number of available connections between a router in a first stage of a multi-stage router network and one or more routers in a second stage of the multi-stage router network. Each of the stages of the multi-stage router network may include a plurality of routers. The method may also include detecting that the number of available connections falls below a threshold number. A notification can be sent to one or more routers in a third stage of the multi-stage router network that the router in the first stage is deprioritized. The one or more routers in the third stage can be operated so that communications to the first stage are routed to one or more other routers in the first stage.

Abstract: Techniques and solutions for distributing routing updates using timing information are described. For example, inter-device messaging protocols can support timing information (e.g., routing protocols be extended to support timing information). The timing information can indicate a time at which the routing update is to be put into effect where the time decreases the further away a given routing device is from the source of the routing update. For example, each routing device can determine a decayed update reference time when the given routing device will put the routing update into effect according to a decay mode. Routing updates can be managed between routing devices that support timing information and routing devices that do not support timing information.

Abstract: Techniques and solutions for distributing routing updates using timing information are described. For example, inter-device messaging protocols can support timing information (e.g., routing protocols be extended to support timing information). The timing information can comprise an indication of a time at which the routing update is to be put into effect. Using the timing information, a number of routing devices can put the routing update into effect at the same time (e.g., at an update reference time) according to a synchronous mode. Routing updates can be managed between routing devices that support timing information and routing devices that do not support timing information.

Abstract: Methods and apparatus for transparent multipath utilization through encapsulation are disclosed. Respective encapsulation packets are generated for at least two different baseline packets transmitted between a source and destination linked by multiple network paths. Each encapsulation packet comprises contents of a corresponding baseline packet, and one or more data values selected in accordance with a path balancing policy. The data values added to one encapsulation packet may differ from those added to another. Different network paths to the destination may be selected for different encapsulation packets of a given transmission based at least in part on the added data values.

Abstract: The following description is directed to configuring network devices. In one example, a deployed configuration for a network device can be collected. The deployed configuration can be representative of a state of the network device at the time of collection. A difference can be detected between the deployed configuration and an authoritative configuration for the network device. In response to detecting the difference, an update of the network device according to the authoritative configuration for the network device can be scheduled.