Talk:Subnet/Archive 1

message: In 
:"Network address 204.4.32.0 Decimal = 11001100.00000100.00100000.00000100 Binary"
shouldn't the last eight digits be all zero?
Snip 14:11, 9 September 2005 (UTC)
replies: text: Yes. Noel (talk) 17:52, 19 September 2005 (UTC)
thread_title: Error in decimal->binary conversion?

message: Putting this here as data for anyone who cares:
The first mention of subnets, in the sense of subdivisions of a classful network, that I know of in Internet documentation occurs in IEN-82, "LCS Net Address Format", from February, 1979. (MIT was using subnets some years before anyone else.) This subnetting scheme, as eventually adopted by the Internet, was more fully described by Jeff Mogul in RFC 917, "Internet subnets", in October 1984.
The notion of subnet masks has to be credited to Dave Moon, though, I think. Although the early LNI hardware supported masks, we didn't really think of using them in the protocol; it was Dave Moon, at an early meeting on an otherwise forgotten piece of technogical detritus named 'MUPPETS' (the name is a play on PARC Universal Packet) - an attempt to deal with the multiplicity of protocol suites inside MIT at the time - who made the mask suggestion at the protocol level, and it was carried forward to Mogul's paper. Noel (talk) 17:52, 19 September 2005 (UTC)
thread_title: Some history

message: The current article says that The 127.0.0.1 Network ID is left out because it is designated for loopback and cannot be assigned to a network. Are there really not more reasons to be mentioned here? It looks very inefficient to take out 224 IP-adresses, and then use only one of them. Bob.v.R 09:03, 15 May 2006 (UTC)
replies: text: 127.* is loopback; I can't see any other reason if all the range already has a known and common meaning. Actually, it's not entirely true that only one of them is used. You can use whatever IP in the range to refer to loopback (and I guess using different IPs has some use). There're other inefficiences in the IP, so why not this one :P --Outlyer 17:48, 15 May 2006 (UTC)
thread_title: Adresses starting with 127

message: In relation to the http://en.wikipedia.org/w/index.php?title=Subnetwork&diff=91277922&oldid=91271869 edit , i agree with moving the image but otherwise please do not edit my edits anymore , concerning your stated reason for censoring my last edit the data was allready stated , which is false , not once does network address translation is mentioned.
I am in the process to rewrite this article in concordance with the Wikipedia:WikiProject_Computer_networking guidelines , and i was pointing out the history of subnets (reasons why it exists , alternatives) data that need to be in the header 
Please comment on the talk page next time you have a issue about my edits not censor them.--Mancini 15:11, 1 December 2006 (UTC)
replies: text: Please see WP:OWN if you don't want your edits edited by other editors, do not edit here. The text you added was already covered further down in the article and it was unnecessary to repeat it in the beginning of the article. I've reinserted the part about the IPv4 shortage. NAT wasn't mentioned down below, but NAT has nothing to do with Subnetworking. However I'd already covered the concept of using fewer addresses by using subnetworks below. I've reinstated that piece as a bit of a summary. If someone doesn't understand subnetworking at all, giving a very brief and technical overview about borrowing bits isn't going to help them. As far as the guidelines go, they're guidelines and not policy regarding computer related topics.--Crossmr 15:24, 1 December 2006 (UTC)
replies: text: I do not have anything against the others , i resent your bad-faith censoring of my edits , i will present new content for voting on this page from now on and seek technical people to override your questionable expertise on the subject.--Mancini 16:24, 1 December 2006 (UTC)
replies: text: I didn't "censor" your edits in bad faith. I resent your bad faith assumption that I was doing it in bad faith. As far as technical expertise goes, if you've got a question about the way I've described something, feel free to ask it. You might also want to read WP:NPA comment on content not the contributors.--Crossmr 16:31, 1 December 2006 (UTC)
replies: text: Whatever reason your edit was non-constructive , Intentionally making non-constructive edits to Wikipedia will result in a block or permanent ban and instead of debating about it ,  i will do as i said and provide new content for voting on the talk page , i am not going to argue with someone that obviously does not even know that in computing a "chunked structure" represents recurrent chunks of slightly variable data--Mancini 16:41, 1 December 2006 (UTC)
replies: text: and attempting to own your contributions or making personal attacks will result in the same thing. My edit was constructive in repositioning an image and removing content that was covered further down in the article. You properly raised the point that perhaps not all of it should be removed and it was put back in. As far as chunks perhaps you should tell google, because "chunked structure" isn't a very widely used term. which seems to mostly have to do with a specific file system type which have nothing to do with subnetworking, and an occasional linguistic reference. Using chunk in that context doesn't properly describe what that is--Crossmr 16:52, 1 December 2006 (UTC)
replies: text: I do not know what the problem is , but you could have said you reposted relevant data , i assummed bad-faith because we should work toghether , your actions point against.Do i really have to give google tips ? try "chunk structure" , it is widely used to describe data , and quite so in networking relating to packet structure , your description of chunk as an unprofessional term in the context is clearly without foundation.--Mancini 17:05, 1 December 2006 (UTC)
replies: text: Packet structure has nothing to do with the process of subnetting a network. The term is not used to describe subnets of a network unless its being used as slang.   I see no evidence that the term is commonly used in regards to subnetting or networks in general, outside of speaking about the content of packets.--Crossmr 17:10, 1 December 2006 (UTC)
thread_title:  edit id 91277922 abusive edit 

message: I don't see the point of a merge here unless its to make the CIDR article huge. I could only see it being merged to have someone suggest that it be split up because both pieces are quite lengthy.--Crossmr 02:31, 4 December 2006 (UTC)
replies: text:  I also dissagree with the merge, quite the opposite should be done and move all info about the subnetting technique to it's own article and improve this one to describe clearly and in detail the subnet/subnetwork concept and it's operation.--Mancini 14:02, 4 December 2006 (UTC)
thread_title:  Merge Suggestion 

message: Several people have been expressing concern that this was hard to understand. I've spent the last 90 minutes rewriting this article in, what I hope, an easier to understand method. I included some binary examples. I found that when I learned how to subnet seeing it as binary really made things easy for me to understand and grasp the concept. I've only copy edited it a small amount, so I'm sure it does require some of that. I've kept the links as I didn't have the time right now to go through them and make sure they all apply and I've kept a few of the paragraphs and one of the tables that was there before. I've tried to lay down a foundation of what a subnet mask is, what a network address is and how they work together. Any comments are welcome.--Crossmr 17:47, 28 November 2006 (UTC)
replies: text: I've re-written the 'Subnets and host count' section to make it (hopefully) clearer and to better represent current practice. I've also removed the section on private addresses as it contained a large number of errors and was largely not relevant to subnetting. Most of the information is already in the IPv4 article - which seems a more sensible place for it (in particular the address ranges used for private IP addresses are not directly relevant to sub-netting). Tjpayne 18:39, 15 April 2007 (UTC)
thread_title:  Rewrite 

message: Currently, the article has the following table:
Class	Leading bits	Start        	End            	Default Subnet Mask in dotted decimal	CIDR notation
A    	0           	0-127.x.x.x  	126.255.255.255	255.0.0.0                            	/8
B    	10          	128-191.x.x.x	191.255.255.255	255.255.0.0                          	/16
C    	110         	192-223.x.x.x	223.255.255.255	255.255.255.0                        	/24
D    	1110        	224-239.x.x.x	239.255.255.255	                                     	
E    	1111        	240-255.x.x.x	255.255.255.0  	                                     	
Shouldn't it be 0-126.x.x.x in the field Start | A? --Abdull 17:23, 10 April 2007 (UTC)
replies: text:  i would argue that although the 127 network only has device-local relevance and therefore cannot be assigned to a network, it is still technically a class A allocation. The table is still wrong, but for a different reason :) Tjpayne 18:52, 15 April 2007 (UTC)
replies: text:  For consistency I've updated this table to use the same one as IPv4 subnetting reference  Tjpayne 14:51, 18 April 2007 (UTC)
thread_title:  Wrong table? 

message: I propose that IPv4 subnetting reference be merged into this. There's redundant information, and the other article seems very incomplete.  —Preceding unsigned comment added by Reinderien (talk • contribs) 02:36, 11 June 2008 (UTC)
thread_title:  New merge suggestion 

message: Are the changes made in this 31 Dec 2008 edit http://en.wikipedia.org/w/index.php?title=Subnetwork&diff=261020601&oldid=260259765 really an improvement? Seems to be a fair bit of material deleted and the opening sentence seems worse. However I do not have the knowledge to know for sure. Nurg (talk) 23:10, 14 January 2009 (UTC)
thread_title:  Please check this edit/deletion 

message: Please move the example with the cable modem near the bottom of the article to be near the top, its the clearest explanation of the concept across the whole article.  If a diagram illustrating the relationships could be added that would really make it clear!  —Preceding unsigned comment added by 65.91.42.118 (talk) 14:23, 7 May 2009 (UTC)
thread_title:  Move the example to be near the top 

message: From the standpoint of a Wikipedia reader (and not an editor), it would make sense that one of the more common subnet mask addresses lead here.  For example, I typed in 192.168.1.1 and it lead to the localhost article.  Should 255.255.255.0 similarly be redirected here?  I would do it myself but I have no idea how to do it.  Thanks for reading  —Preceding unsigned comment added by 207.255.210.182 (talk) 14:24, 10 May 2009 (UTC)
thread_title:  Should 255.255.255.0 lead here? 

message: I came to the page looking for answers and information for implementing subnets, this page didn't really help.  While it may be very useful in some categories, and KUDOS to those editing it, it is missing a section on how to implement subnets.  Sure subnets are useful, here is what they are useful for, here are some changes occurring in the networking space, etc.  Where is the implementation section?  How to use a subnet.  Think of your audience as technically inclined individuals who are trying to set up home networks, or office networks that don't feel like calling the cable guy. eximo (talk) 22:22, 12 October 2009 (UTC)
replies: text: WP is not a how-to manual. See WP:NOTHOWTO Kbrose (talk) 02:10, 13 October 2009 (UTC)
thread_title: Implementation section

message: per request. Not suitably reference (only 4 at the time of writing!). Airplaneman talk 05:14, 14 November 2009 (UTC)
replies: text: Perhaps this editor should actually read the article and not only look in one place. Article contains enough references, in addition to inline RFC references to support the subject, given that it is a narrow topic. Reverted action.Kbrose (talk) 14:48, 14 November 2009 (UTC)
thread_title: C-class reassessment

message: This article is way too confusing and haphazard. A far better and to-the-point explanation about subnets and masks and what those numbers mean is here:
http://www.iplocation.net/tools/netmask.php  — Preceding unsigned comment added by 24.22.219.163 (talk) 12:01, 23 July 2012 (UTC)
thread_title:  Very confusing article 

message: I'm not going to make the edit in the article for fear of not being clear enough. :) But I will add it here. 
What might help people is seeing how the bits get added up. Everything progresses rather logically when you look at it in binary but it's the translation to decimal that makes everything look so random. 
Bit 1	Bit 2	Bit 3	Bit 4	Bit 5	Bit 6	Bit 7	Bit 8
0    	0    	0    	0    	0    	0    	0    	0
128  	64   	32   	16   	8    	4    	2    	1
With no bits selected, the value is 0. 
Bit 1	Bit 2	Bit 3	Bit 4	Bit 5	Bit 6	Bit 7	Bit 8
1    	1    	1    	1    	1    	1    	1    	1
128  	64   	32   	16   	8    	4    	2    	1
1+2+4+8+16+32+64+128=255 
Bit 1	Bit 2	Bit 3	Bit 4	Bit 5	Bit 6	Bit 7	Bit 8
1    	1    	0    	0    	0    	0    	0    	0
128  	64   	32   	16   	8    	4    	2    	1
128+64=192
This should make the whole idea of borrowing bits here and there more sensible. 
--Gmuir 13:40, 17 May 2007 (UTC)
replies: text: Some changes could be done, and thanks to your message I generally feel more compelled at changing the article a bit or adding an example of some sort. (generally) Logictheo 20:58, 2 June 2007 (UTC)

text: I'm sure there must be an article on wikipedia about binary numbers. This is an article about what a subnetwork is, not a guide on binary numbers. If explanation is required on this subject it can be linked to.--Crossmr 16:35, 3 June 2007 (UTC)
thread_title: It might help to have an explanation of how the octets add up

message: "When Foo sends data to example.com at 208.77.188.166, the router performs a logical AND of the destination example.com address with the subnet mask. It also performs a logical AND of the origin address (17.76.99.1) and recognizes that these two results are different, and therefore sends the data over the Internet, via the subnet's default gateway."
"It also performs a logical AND of the origin address (17.76.99.1)" It performs a logical AND with the origin address and what?  AND operations involve two cases.  It would also help to have the binary code stacked on top of eachother so you do the AND operation for yourself in your head more easily.173.70.15.67 (talk) 14:24, 13 September 2009 (UTC)
thread_title:  Clarify AND operations 

message: "For example, 255.255.255.0 is the network mask for the 192.168.1.0/24 prefix."
while this is true, 255.255.255.0 is the network mask for anything that ends in 0. so it's also the mask for 208.33.47.0 a more accurate mask would be 192.168.1.0. applying that mask to anything in the 192.168.1.0/24 range will always yield 192.168.1.0 (so 192.168.1.101 masked with 192.168.1.0 will yield 192.168.1.0 but 208.33.47.0 masked to 192.168.1.0 will yield 208.33.47.0 and thus not be routed with this mask  — Preceding unsigned comment added by 74.84.117.50 (talk) 18:35, 18 April 2013 (UTC)
thread_title: somewhat misleading

message: As noted under "Routing prefix" above, the article is still (or once more) inconsistent in its terminology. The intro now refers to "the network number or routing prefix" but the diagram uses network identifier and the later tables refer to network prefix. I don't have the subject expertise (or, it appears, the Inkscape expertise – see :File:Subnetting Concept-en.svg) to fix it. Dave.Dunford (talk) 13:51, 16 February 2019 (UTC)
thread_title:  Inconsistency: "routing prefix", "network number", "network identifier", "network prefix" 

message: This was referred to as network number, routing prefix and network prefix. For consistency and clarity, I've changed all to routing prefix (and prefix for short) because that's what was predominantly used in the article. We probably want to go with the term used predominantly in the literature. I'm thinking that's network number but I'd like to solicit opinitions and citations on this. --Kvng (talk) 21:15, 4 October 2010 (UTC)
replies: text: Now says, "48-bit (/48) prefix." Seems like a legit fix. ~Kvng (talk) 15:19, 14 May 2020 (UTC)
thread_title:  Routing prefix 

message: It is still impossible, by reading this article, to understand what a subnet mask is (beyond (in IPv4 at least) the fact that it is a 32 bit number) and what it actually does. This confusion may be caused by trying to relate what is written here to many (most?) people's experience of a subnet mask as being a mysterious dotted quad in their Windows network adapter's configuration which seems to serve no purpose (I can set mine to any acceptable number greater or equal to 254 and everything still works), and is never explained in MS help.
It would help if there could be some explanation of what the subnet mask actually does on a single system using an IP address exclusively?
What does it do if you have a single internet connection and, say, 6 computers attached to a router?
In which pieces of equipment is the mask actually used and what does it do in each?
I have a suspicion that this is one of those articles that makes perfect sense if you already know what a subnet mask is but is absolutely opaque if you don't. PRL42 (talk) 17:10, 30 June 2014 (UTC)
replies: text: Our definition in the current lead is, "...subnet mask or netmask, which is the bitmask that when applied by a bitwise AND operation to any IP address in the network, yields the routing prefix." This definitely could use some improvement. ~Kvng (talk) 15:19, 14 May 2020 (UTC)
thread_title:  Still as clear as mud 

message: This article needs a lot of improvement. It states the same common simple basics, and leaves unclear the crucial practical implications.
My current understanding is this: each network device starts with a MAC address and sooner or later has an IP address and a subnet mask. Ordinarily the subnet mask would be configured to be consistent with all the other locally directly connected devices; if not, the situation is complicated and confusing. But in the simple ordinary case, the subnet masks will all be consistent within the local network. Each time each device wants to initiate a communication, it uses the subnet mask to calculate whether the other party it wants to reach is in the same subnet. If it thinks so, it uses a simple set of local methods to communicate rather directly. But if it thinks the other party is not in the same subnet, then it will try to use completely different indirect methods, by reaching out to a gateway etc in hopes of eventually reaching the desired party. This seems to be the key practical significance of subnet masks. If this is true, the article should clearly convey this key significance.
It may also be that within subnets most communications are by ARP MAC and between subnets most by IP, which is pretty simple and important to understand and worth stating in the article, if so. -71.174.178.251 (talk) 18:08, 4 July 2014 (UTC)
replies: text: Your understanding is correct. Network prefix and subnet mask should be the same for all devices on a subnet. The prefix and mask are used to determine local vs. remote nature of destinations. Some of these points are touched on in the lead but addressing their purpose directly as you have suggested, would be an improvement. ~Kvng (talk) 15:19, 14 May 2020 (UTC)
thread_title:  each device has own concept of own subnet 

message: When was subnet addressing added to IPv4? We should probably also say when CIDR was added. I almost remember before subnets, but not close enough. Gah4 (talk) 06:15, 9 September 2021 (UTC)
thread_title:  when?