A bridge system is necessary when direct network connectivity is not available between the initiating and target systems. When bridge systems are configured on a link, all data transferred between the initiating and target systems flows through the nodes of the bridge systems. You can add up to four bridge systems in the link between data source nodes in initiator and target systems. The nodes in a bridge system consist of one of the following:
- A subset of data source nodes running Teradata Fabric node software. The data source nodes can be an initiator system, target system, or both.
- A set of non-data source nodes running Teradata Fabric node software. The non-data source nodes do not need connector software because there is no local data to process. An example of a non-data source node is an edge node in a Hadoop system.
For each bridge system added to a link, a new hop configuration is required that specifies the initiating side network, target side network, and the communication policy to use for the data transferred for that hop. A hop is the transfer of data between two directly connected data source or bridge systems. The number of hops is based on the number of bridges.
| Number of Bridges | Number of Hops Defined |
|---|---|
| No bridge | One hop (the hop between the initiator and target) |
| One bridge | Two hops (the hop between the initiator and bridge, and the hop between the bridge and target) |
| Two bridges | Three hops (the hop between the initiator and the first bridge, the hop between the first bridge and second bridge, and the hop between the second bridge and target) |
| Three bridges | Four hops (the hop between the initiator and the first bridge, the hop between the first bridge and second bridge, the hop between the second bridge and third bridge, and the hop between the third bridge and target). |
| Four bridges | Five hops (the hop between the initiator and the first bridge, the hop between the first bridge and second bridge, the hop between the second bridge and third bridge, the hop between the third bridge and fourth bridge, and the hop between the fourth bridge and target). |