Why a glossary
Shopping for DMIT or comparing cloud servers means repeatedly meeting terms like CN2 GIA, CMIN2, Eyeball and Looking Glass. They directly determine route quality and price gaps. This glossary groups them into "network routes → product & billing → testing tools" so you can align concepts quickly while reading plan pages and reviews.
Network routes
| Term | Meaning |
|---|---|
| CN2 GIA | China Telecom's premium Global Internet Access network — dedicated path with optimised return routes; the most stable at peak and the most expensive. |
| CN2 GT | China Telecom CN2 transit — outbound via CN2 but return partly on the regular 163 backbone; quality between GIA and standard routes. |
| 163 backbone | China Telecom's regular long-haul network (AS4134) — huge capacity but congests at peak; the most common default route. |
| CMIN2 | China Mobile International Premium network — optimised return for China Mobile users. |
| CUII (AS9929) | China Unicom International Premium network ("9929") — optimised return for China Unicom users. |
| Tier 1 | DMIT's standard international series — no China return optimisation, largest traffic quotas, lowest unit price. |
| Premium | DMIT's optimised-return series with CN2 GIA / CMIN2 / 9929 backhaul, tuned for mainland China access. |
| Eyeball | DMIT's return-route series tuned for residential ("eyeball") visitors, currently exclusive to Hong Kong. |
Product & billing
| Term | Meaning |
|---|---|
| vCPU | Virtual CPU cores allocated from physical cores via virtualisation; drives concurrency capacity. |
| Burst | Mechanism allowing short spikes above nominal performance before falling back to baseline. |
| Traffic quota | Outbound/bidirectional traffic cap per billing cycle; overage handling per official plan page. |
| Port speed | Instance NIC bandwidth cap such as 1Gbps / 10Gbps — a peak rate, not a guarantee. |
| /64 IPv6 | An IPv6 allocation unit; DMIT instances ship with one /64 prefix by default — vastly more addresses than needed. |
| rDNS (PTR) | Reverse DNS record for an IP; required for mail sending, settable via support ticket. |
Testing tools
| Term | Meaning |
|---|---|
| Looking Glass | Provider-hosted test page that runs ping / traceroute / mtr from the datacenter side — the first stop before buying. |
| mtr | Combines ping and traceroute to continuously watch per-hop packet loss. |
| Traceroute | Shows the routing path; used to verify optimised return routes (59.43.x.x hops indicate CN2). |
| iperf3 | Measures real bandwidth between two machines; validates port speed. |
| TTFB | Time To First Byte — total of latency plus server processing; a good end-to-end health metric. |
Using this table to decide
- Audience mainly in mainland China → compare Premium / Eyeball series (see Network Series Guide)
- Overseas or global audience → Tier 1 offers better value (see Plan Value Analysis)
- Before purchase → test from your own carrier via Looking Glass (see Location Comparison)
Related articles
Network Series Guide, How to Choose, VPS vs Cloud.
Data checked: 2026-08-18. Route naming follows official DMIT documentation.