CONGA is a global collision awareness load balancing technique that aims to minimize delays on the network due to link failures. It is implemented in the ACI data center fabrics and uses overlay header encapsulation, a link path to destination table, and a 3-bit metric system. The design involves endpoint servers sending packets encapsulated with an overlay header and congestion metric to spine switches, which forward the packets to the destination leaf switch based on the header information stored in its path table.

1. Transport Protocol in
Data Center
Authors:
Abdoulaye Diop, Mostafa Fetouh, Suleiman
Adams

2. CONGA
• It is a Global Collision Awareness
Load Balancing technique
• Its purpose is the minimize delays
on the network due to link failure
• It is implemented in the ACI of
Data Center fabrics
• Uses:
• Overlay Header
Encapsulation
• @Link Path to Destination
Table
• 3-Bits metric system

3. CONGA
DESIGN-1
• endpoint (server or
VM) sends a packet
to the fabric
• encapsulates the
packet
• The spine switches
forward the packet
to its destination
leaf based entirely
on the outer header

4. CONGA
DESIGN-2
• Congestion metric in the
overlay header
• The metric is updated hop-
by-hop
• This information is stored at
the destination leaf on a per
source leaf, per path basis

5. CONGA
DESIGN-3

6. CONGA
DESIGN-4

7. CONGA
DESIGN-5