I hear that the C block of an IP is the xxx in 59.462.xxx.21 Does anybody know why this is bad or potentially bad from a link popularity point of view. Look forward to the education on this topic.
I believe that SEs like google discount the value of links if they are all or most coming from the same C-Block. This IMHO is one way to try and curb the link buyers and sellers in googles eyes. Think about it for a sec. About a year ago most of the links you purchased if you did were all on the same site which meant that they were all on the same C -Block, but it was at that time and maybe even a little now manipulating the serps and all in anchor values with google. Plus durning this time there were a lot of seos that had several sites with 10s of thousands of pages all on the same host and same C- Class. Google has already stated that purchasing links is a no no, so again IMHO this is the reason for a filter to discount the values and maybe even cause a penalty for A LOT of links coming from the same C-Block
Oh, you mean if a link broker like www.linktextpopularity.com sells links to you from their page, then that's not good? Because isn't a C block a webpage that has a bunch of links on it? Can anyone give me a visual of a website that is a C block? I have a tough time trying to grasp this concept.
A C-Block is not a website but a set of IPs that all have a same set of octaves. As an example lets say your IP is 45.44.43.42 the .43 is the start of that C-Block so anything like 43.43 or 43.44 or 43.45 and so on would be the same C-Block. You could have website A on 45.44.43.42 and have another website B on 45.44.43.1 and they would both be on the same C-Block. The C-Class is indicated by the third set of numbers within a C-Block. To give you an example of changing that C-Block that would be 45.44.44.42 that would be a different C-Block than the example I gave above. Hope this helps.
I think you've gotten some incomplete information -- every Web site has a "C" block - it's just the third set of numbers in your IP address. I think Las Vegas Homes has it right in post 2 - whomever you heard this from was probably talking about the assumption that the search engines discount your site if all of your backlinks are coming from the same web site or groups of web sites (i.e. sites that are all owned by the same person).
Its not IMHO sites that are owned by the same person because their are ways of masking that, its links coming from the same set of C-Blocks that I believe gets your links discounted. I mean none of us are stupid nor are the SEs if you have the same content, the same theme and links from the same C Class then one can assume that it is owned by the same person but that is not always the case. You may have as an example 2 webmasters who purchased and use the same server but they both have the same C Class for their IPs and link between eachother. I dont claim to know a lot about this subject but it is just my humble opinion with what little knowledge I do have.
>>>>(i.e. sites that are all owned by the same person). Oh, you mean another way of saying this are sites that are on the same server as well? I"m really not this dumb. Really. Just have no clue about IPs and server protocol. But do understand other stuff about SEO
Not to throw fuel on the fire lol but one server can have multiple C-Blocks. Sites on the same server can have different C Blocks if they are assigned to that server.
Let me try and straighten some of this information out. I'm not an absolute expert, but here is my understanding. 1. There are 256 IP addresses in a C block. Rather than being the second last group of numbers as suggested I believe it is the first three sets of numbers so that a C block would be aaa.bbb.ccc.0 to aaa.bbb.ccc.255. This is 256 IP addresses in total. 2. What use to happen is people would register multiple domains simply to have them cross link back and forth to each other. The probablity was, or is that these domains would all be hosted on the same server and would all use addresses in the same C block. Servers can have more than one block of IP addresses, but people never thought about giving IPs from separate C blocks to each domain or web site. So we think Google has concluded that sites all from the same domain that heavily interlink may exist simply for the linking value. 3. Nothing is necessarily "bad" about linking between site hosted on the same C block, but the value of the link for SERP placement may not be as great as the value of a link from a site residing on a different C block.
The IP number we normally use is a decimal representation of a 32 bit binary number. Thats why the numbers you see always have values between zero and 255. In the interest of administrative efficiency the powers that assign IP numbers created class A, B and C subnets. If you are an entity who frequently needs IP numbers you can apply for one of these and then assign the individual IP numbers as you please. For example, the Univ. of New Mexico has a class B subnet so 16 of the 32 bits are theirs to assign as they see fit. This allows them to assign blocks of numbers to various colleges and simplifies recordkeeping and trouble shooting. A class C subnet is the smallest group and has 32 IP's. Many small ISP's would get one or more class C subnets and then assign the individual numbers to their customers. This all made good sense in the days before internet use exploded. You may remember a few years ago when there was a lot of concern about running out of IP numbers. You don't hear as much about that now because they figured out how to get more mileage out of the existing numbers. Now a single reseller server at your friendly neighborhood ISP has a single IP number and may host 400+ domains. I read the posts about making sure your sites are on different class C subnets, but I have to wonder... If the ISP loads 400 domains per server (many do more) and they fill their address space, there will be more than 12,000 domains in the same "C block". I'm not convinced this provides Google with much useful data for detecting artificial crosslinking between related sites. If you consider the real "Pros" at this stuff probably have their own servers it would (IMHO) be much more entertaining/effective for Google to spend some effort researching the IP's assigned to EV1 or other large hosting companies. Given the abundance of data contained in packet headers, penalizing class C subnet blocks seems terribly primative and prone to false positives.
Is the idea to encourage people to get BLs from a variety of sources, potentially not associated with each other?
I would suggest you focus on good quality relevant backlinks and not worry about c-block, c-class, and the like... much ado about nothing, IMO.