Flows, Links, and Connections
Network Visibility can collect metrics for these object types:
- Network links between tiers, or between tiers and load balancers/TCP endpoints
- Connections between nodes, or between nodes and load balancers/TCP endpoints
Troubleshooting a performance issue in Network Visibility often involves drilling down from an application issue (flow) to a network issue (link) to the root cause (connection). See Workflows and Example Use Cases.
Application Flows
App Agents collect metrics forapplication flowsbetween tiers, as shown in the Application Flow Map. This diagram shows the calls, transactions, and messages for applicationxbetween tier 1 and tier 2.
Network Links
Network Agents collect metrics fornetwork links, which you can view in the Network Dashboard. A network link is the set of all traffic between two tiers, or between a tier and an intermediate load balancer, or TCP endpoint. If an application flow transports traffic through a load balancer, Network Visibility creates a link on each side and calculates metrics for each link. This diagram shows the network traffic for applicationxsent and received by the two tiers through a load balancer.
TCP Connections
Individual nodes send and receive traffic over connections. In Network Visibility, a connectionis a set of all traffic with the same source IP address, destination IP address, destination port, and protocol. This diagram shows the individual connections used by the four nodes to send and receive traffic for applicationxthrough the load balancer.