# Technical Architecture

## What is Anycast

| |Scenario|Packet Replication|Receiver|
|---|---|---|---|
|Unicast|Unicast|Communication from a single source to a single receiver|No need for replication|A single receiver|
|Mutilcast|Multicast|Communication from a single source to several receivers|Multiple copies needed|Multiple receivers, managed by multicast protocols such as IGMP|
|Broadcast|Broadcast|Communication from a single source to all resources within its subnet|Multiple copies needed|Multiple receivers, being all resources within the subnet (when no VLAN isolation is present)|
|Anycast|Anycast|Communication from a single source to a group of receivers, but the actual receiver is still one, determined by routing protocol|No need for replication|A group of receivers. This group of receivers declares the same address to the Internet, and the routing protocol determines which server the packets are sent to.|

## Differences from Ordinary EIP

* Ordinary EIP: Declared in a single Region, global players need to access across Regions via the public network. High latency, high jitter.

* Anycast EIP: Declared in multiple Regions, global player users access the Genesis Cloud backbone network from the nearest point and complete the transmission via the Genesis Cloud dedicated line. Low latency, low jitter.


## Global Acceleration
#### Outgoing Traffic

* Transmitted directly to the public network through the source Genesis Cloud node.

#### Incoming Traffic

* Inter-room backhaul: Public network routing uses BGP to select the route, chooses the appropriate room entrance according to the principle of proximity, and sends the traffic to the corresponding POP point of Genesis Cloud, and then completes the backhaul through the dedicated line.

* Backhaul in the same room: The public network is routed to the POP point in the same room, and then the backhaul is completed through UVER transmission.