First let us know about cdn. The next content list as follows from wiki.
A content delivery network or content distribution network (CDN) is a globally distributed network of proxy servers deployed in multiple
data centers. The goal of a CDN is to serve content to end-users with
high availability and high performance. CDNs serve a large fraction of
the Internet content today, including web objects (text, graphics and
scripts), downloadable objects (media files, software, documents),
applications (e-commerce, portals), live streaming media, on-demand
streaming media, and social networks. The term CDN means many things to different people and is an umbrella
term that covers a lot of different types of content delivery
services. Video streaming, software downloads, web and mobile content
acceleration, licensed/managed CDN, transparent caching, and services
to measure CDN performance, load balancing, multi-CDN switching and
analytics and cloud intelligence. It’s a complex ecosystem with a lot
of vendors both large and small and some CDN vendors cross over into
other industries like security and WAN optimization. Content owners such as media companies and e-commerce vendors pay CDN
operators to deliver their content to their end-users. In turn, a CDN
pays ISPs, carriers, and network operators for hosting its servers in
their data centers.
How to get the CDN service?
At home, you can try to use baidu CloudSpeed which is free.
just check the info and change the dns as it provide on your domain register site.
but if you were not in China, you can see this link Ten free cdn for wordpress
Here the question come:
How could we get the real ip of the server instead of cdn?
- let us try ping it, actually we know that ping may not work for the without www child domain, so you should ping like xxx.cn not www.xxx.cn.This because many operators did not provide the www cdn service.
- since we mention the second-level domain, you should try all the possible child domain.(whatever the way you choose, alexa , chinaz, or any tool could brute force… )
- find the history (How about netcraft.com)(espically this way, I found the target Ip from ip138 history)
- still ping, but with vpn or any foreign proxy.
- guess the
phpinfo（It seems seek far and neglect what lies close at hand, anyway it is a good idea.）
- The last but effective significantly method is e-mail. For example, you can register account on the target site. Most of them will send you an email to you. You can check the real content in it to find its real IP.
Finally, share a poem for you: ｜声声慢 Tune: ”Slow, SlowTune” 寻寻觅觅
I look for what I miss
I know not what it is 凄凄惨惨戚戚
I feel so sad, so drear,
So lonely, without cheer 乍暖还寒时候
How hard is it
To keep me fit
In this lightering cold! 三杯两盏淡酒
Hardly warmed up
By cup on cup
Of wine so dry
Oh, how could I
Endure at dusk thedrift
Of wind so swift? 雁过也
It breaks my heart,alas!
To see the wild gees pass
For they are my acquaintances of old. 满地黄花堆积
The ground is coveredwith yellow flowers
Faded and fallen in showers
Who will pick them upnow? 守着窗儿
Sitting alone at thewindow
How could I butquicken
The pace of darknesswhich won’t thicken? 梧桐更兼细雨
On parasol-trees leaves a fine rain drizzles
At twilight grizzles
Oh! what can I do with a grief