1. Basic Concepts
First of all, the traditional 163 backbone network and China Telecom direct CN2 lines (CN2 GT and CN2
GIA) are both networks intended for China Telecom. If it is triple-network CN2, that means China Mobile and China Unicom will also use China Telecom’s CN2 lines. Generally, the traffic will hop to a China Telecom CN2 node within mainland China first, and then go through the international exit, thereby benefiting from the CN2 line.
CN2, the full name of which is Chinatelecom Next Carrier
Network (CNCN), is abbreviated further as CN2. As a “premium network project” launched by China Telecom, its line quality is definitely better than the traditional 163 backbone network.
At present, China Telecom’s international exits generally have 3 types of carrier network, including the traditional 163 backbone network, CN2
GT lines, and CN2 GIA lines:
- Traditional 163 backbone network: This is the most common and most basic line, also called ChinaNet(AS4134). It is not optimized for China Telecom users, and this is generally the carrier network type used (202.97 nodes throughout the whole route). Because many people use it and the line is not optimized, congestion and high packet loss often occur during peak evening hours.
-
CN2 GT line: GT stands for Global Transit. CN2
GT is also a type of CN2 line, but it is a mid-tier product among CN2 lines and ranks relatively low within CN2. Traditional 202.97 nodes will appear on both the outbound and return routes. Generally speaking, both 202.97 and 59.43 nodes will appear, and only the international exit will use the 59.43
CN2 node. Because the CN2
GT line includes high-speed 59.43 nodes, CN2(AS4809), its line quality is better than the traditional 163 backbone network. -
CN2 GIA line: GIA stands for Global Internet
Access. CN2
GIA is naturally also a type of CN2 line, and it is the high-end product among CN2 lines, ranking the highest within CN2. Both the full route and the return route use high-speed 59.43 nodes throughout, CN2(AS4809). CN2
GIA lines are generally more stable, faster, and have lower packet loss.
Line ranking:
- CN2 GIA ranks first in speed and network quality (preferred choice)
-
CN2 GT ranks second in speed and network quality
(second choice) -
Traditional 163 backbone network ranks third in speed and network quality
(it can open websites, but watching videos is a very poor experience)
Below, we use https://tools.ipip.net/traceroute.php
to test how to determine which server line is better.
Here, we use CN2 GT and CN2 GIA for comparison.
Test environment: both are Singapore 30M broadband
opening the same 4K YouTube video link
Below is a YouTube video opened via CN2 GIA, with a CONNECT SPEED of 55217
Kbps
Traditional CN2 GT line opening a YouTube video CONNECT SPEED is 8429 Kbps
From the test above, the link speed difference between CN2 GIA and CN2 GT is about 10 times. With the same 30M connection, CN2 GIA can play 4K smoothly,
while 30M CN2 GT stutters badly when playing 4K, and CN2 GT also suffers from severe packet loss.
How can you tell whether your VPS server is CN2 GIA or CN2 GT?
Tool used: route detection tool
https://tools.ipip.net/traceroute.php
CN2 GIA route test image: it goes through the 59.43 provincial-level route
CN2 GT goes through the 207.97 route
Return route test:
Generally, our overseas machines are Linux machines. Since Linux
displays things in command-line form, it cannot be shown directly on a web page. So here we need to use a script.
wget --no-check-certificate https://raw.githubusercontent.com/xiaohouzivpn/script/master/besttrace chmod +x besttrace &&./besttrace
For example, let’s test the route to the IP 106.13.198.73
./besttrace -a 106.13.198.73
As you can see from the image above, the 59.43 segment is the CN2
GIA route. This type is relatively more reliable.