One question to start, What's the VMS you are using?
Btw, no recommendations of other camera manufacturers. Let's stick to what Tarek is looking for unless he says he is open to alternatives.
As John asked urge VMS you are using should help determine that. Not all VMS's will support the GeoVision Cameras.
I trust Samsung a lot more than GeoVision.
for samsung i will use samsung security manager its free CMS
and for geovision i will use their free vms software , so in both its free VMS
Also I have another option - ACTi + Nuuo NVR.
I have used a few different models of Geovision IP cameras and have been very impressed by them. Build quality is excellent, nice feature set, installer friendly. They also seem to roll out upgraded firmware fairly often. They definitely warrant serious consideration.
"Free" VMS is almost always a bad idea. How do you intend to access your video (client, browser, mobile apps)? How many people will have access to the video? Have you run the numbers on the WAN bandwidth requirements for remote access? Is remote review of archived video a feature you intend to use? These are just some of the questions you need to answer before finalizing a purchasing decision. Cameras are just a part of the total solution and "Free" usually means you get what you pay for.
Free VMSes are fine so long as the use case is not too sophisticated. At 100+ cameras, this does raise some concern as bigger deployments tend to want (or need) higher end features.
If you go Samsung and then later want to switch to a higher end, open VMS, that should be fairly easy to do, as they have fairly wide support. On the other hand, Geovision only lists 2 cameras currently supporting ONVIF and those are not the ones on your list.
Remote view is generally not a problem. Whether the VMS is paid or free, the WAN bandwidth remains the same. Some VMSes may be better with remote view but it's not always based on what you pay.
The bigger thing to me is management of the cameras. How many servers will these 100 cameras be run on? 1, 2, 3, 4? How will you manage across servers? Are there any limitations on accessing cameras across servers, etc.?
John makes some good points concerning camera density per server but also know that remote viewing can be a huge problem if you plan on using it. Consider that a single 1.3 MP camera is cranking out an avg data rate of 2.0Mbps at 10fps. If you are streaming two cameras that number obviously doubles to 4.0Mbps and this applies to each remote connection. Run a bandwidth speed test at your site to determine the avg upload speed and do the math based on your own camera count. Some VMS solutions take advantage of the multi streaming capability of most cameras to provide a degraded live view at a smaller data rate. Remote playback of full resolution archived video generally comes with the full file size and can easily overwhelm most WAN connections. At that point break out the sundial and watch any other processes depending on that upload bandwidth come to a grinding halt.
You don't need multistreaming for remote monitoring. It's definitely nice to have but even without it, almost all VMS clients will frame drop for live video (you'll still be able to stream but it will be a slide show, with 1fps or 1 frame every few seconds but at full resolution). If you are doing investigations over a remote connection, it will take some time to download the video but you will want to have the full resolution stream, not a low res version.