CSS routes global push and playback traffic based on DNS resolution by default. This is a common and simple method. However, DNS resolution errors and cross-network traffic occurrences are common due to the complexity of global network environments. We recommend you use Tencent Cloud’s HTTPDNS to optimize traffic routing for live streaming.
An ISP's local DNS egress performs NAT based on an authoritative DNS destination IP address or forwards the resolving request to other DNS servers. This makes it difficult for the authoritative DNS server to correctly identify the IP address of the ISP's local DNS, resulting in resolution errors and cross-network traffic. Tencent Cloud’s HTTPDNS service is powered by leading DNS cluster technologies and supports multi-ISP routing and custom routes.For more details, please refer to HTTPDNS.
Note:
This document shows you how to use HTTPDNS to optimize traffic routing for live streaming across the world. For details about the HTTPDNS API used, see Querying with HTTP Request Methods.
Use an HTTP GET request in the format of http://119.29.29.98/d?dn={$push_domain DES-encrypted string}&ip={$ip DES-encrypted string}&id=$id to request a push IP address from HTTPDNS.
ip indicates the public egress IP address of the requester. This field determines the region and ISP of the IP address to which traffic is routed. It also needs to be encrypted using the DES algorithm.
id indicates the authorization ID, which uniquely identifies a user.
Decrypting the IP address
The data obtained from HTTPDNS is DES-encrypted. Decrypt it to get the IP address (server_ip). For details, see AES/DES Encryption/Decryption.
Splicing the push URL
The format of a push URL is rtmp://server_ip/live/streamname?txTime=xxx&txSecret=xxx&txHost=domain. server_ip is the push IP address obtained in the previous step. txHost (important) is the domain you use for push.
Routing Playback Traffic Using HTTPDNS
Requesting the playback IP address
Use an HTTP GET request in the format of http://119.29.29.98/d?dn={$domain DES-encrypted string}&ip={$ip DES-encrypted string}&id=$id to request the playback IP address from HTTPDNS.
The public egress IP address of the requester. This field determines the region and ISP of the IP address to which traffic is routed. It also needs to be encrypted using the DES algorithm.
id
The authorization ID, which uniquely identifies a user.
Decrypting the IP address
The data obtained from HTTPDNS is DES-encrypted. Decrypt it to get the IP address (server_ip). For details, see AES/DES Encryption/Decryption.
Splicing the playback URL
HTTP: The formats of HTTP playback URLs for FLV and HLS are as follows (server_ip is the playback IP address obtained in the previous step and play_domain is the playback domain):
RTMP: The format of an RTMP playback URL is as follows (server_ip is the playback IP address obtained in the previous step and play_domain is the playback domain):
There is a small likelihood of HTTPDNS request errors. If your request times out or the result returned is not an IP address or is empty, please perform resolution at the local DNS server.
Since IP does not support HTTPS, this solution is not currently supported for optimized scheduling.
