Transient loop prevention in a hybrid layer-2 network

An apparatus, comprising:

• one or more network interfaces adapted to communicate with a first network of a second protocol;
• one or more network interfaces adapted to communicate with a first network of a first protocol, the apparatus interconnected via the first network of the first protocol with a second apparatus, the second apparatus at a border between a second network of the first protocol and a second network of the second protocol, the first and second networks of the first protocol being interconnected;
• a processor coupled to the network interfaces and adapted to execute one or more processes;
• and
• a memory configured to store a hybrid network boundary switching process executable by the processor, the switching process when executed operable to:
• detect a merge of the first and second networks of the second protocol;
• and
• in response to detection of the merge of the first and second networks of the second protocol:
• block data packets from traversing through the one or more network interfaces adapted to communicate with the first network of the first protocol;
• allow protocol messages to flow between the first and second networks of the first protocol through the one or more network interfaces adapted to communicate with the first network of the first protocol;
• allow the first and second networks of the first protocol to discover each other through the protocol messages and to prevent a loop;
• and
• in response to allowance of the first and second networks of the first protocol to discover each other, unblock the one or more network interfaces adapted to communicate with the first network of the first protocol to allow traversal of data packets.

An apparatus, comprising:

• one or more network interfaces adapted to communicate with a first network of a second protocol;
• one or more network interfaces adapted to communicate with a first network of a first protocol, the apparatus interconnected via the first network of the first protocol with a second apparatus, the second apparatus at a border between a second network of the first protocol and a second network of the second protocol, the first and second networks of the first protocol being interconnected;
• means for detecting a merge of the first and second networks of the second protocol;
• means for blocking data packets from traversing through the one or more network interfaces adapted to communicate with the first network of the first protocol in response to a detected merge of the first and second networks of the second protocol;
• means for allowing protocol messages to flow between the first and second networks of the first protocol through the one or more network interfaces adapted to communicate with the first network of the first protocol in response to the detected merge;
• means for allowing the first and second networks of the first protocol to discover each other through the protocol messages and to prevent a loop in response to the detected merge;
• and
• means for unblocking the one or more network interfaces adapted to communicate with the first network of the first protocol to allow traversal of data packets in response to allowing the first and second networks of the first protocol to discover each other through the protocol messages and to prevent a loop.