republican-creole
Search:  

 
 
   All ForumsHot TopicsGallery






how-to block ads


 
Forums » Up and Running » Networking » How do I determine subnet manually?
Search Topic:
Share Topic:
RSS topic:
toggle:
flat / full
normal / watch
Posting:
Post a:
Post a:
[XP] Need new NIC »
« Any way to set a "Hard" Cap with router?  
AuthorAll Replies

verifone411

join:2008-05-08

reply to IamGimli
Re: How do I determine subnet manually?

Thanks for the infomation. Sticking with the first class b number (does that change things since you decided to move the example to a class c?)

How do you know and how do you determine that...

/24 = 256 IPs = 254 Usable ? i know the diagrams say that.

Is it because the last 2 sets of octects represent 8 bits each for a total of 16. Each 16 bit placeholder can have 2 different values so that is why you raise it to the power of 2? to get 65536- 2=65534 usable?


tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
·Hollis Hosting
·Verizon Online DSL
·Fairpoint Communic..

Each octet is 8-bits. A /24 address means 24-bits of address are reserved for network leaving 8 for host. This assumes you are talking about IPv4 with a 32-bit address range.

An Octet is FFh or 256 (in decimal notion) However, since the lowest address is reserved as network address and highest for broadcast that leaves 254 available host addresses.

Dotted Decimal was a convenient way to represent IP address when Class-full addressing was used since Class boundaries were also octet boundaries. With the advent of classless routing where split between network and host address can occur anywhere dotted decimal is a little like using Roman numerals to build a house.

If you stick with binary or hex it is a lot less confusing.

/tom

IamGimli

join:2004-02-28
Canada
·Primus Talkbroadband
·B2B2C High-Speed I..

said by tschmidt See Profile :

If you stick with binary or hex it is a lot less confusing.
I understand binary but how is hexadecimal any less confusing than decimal to represent network addresses? It may make them a bit shorter to write but I don't see any difference in the confusion aspect.


tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
·Hollis Hosting
·Verizon Online DSL
·Fairpoint Communic..

said by IamGimli See Profile :

I understand binary but how is hexadecimal any less confusing than decimal to represent network addresses? It may make them a bit shorter to write but I don't see any difference in the confusion aspect.
Dotted decimal represents a discontinuous counting method. If I add 1 to FFh I get 100h. If I add 1 to 0.255 (dotted decimal) I get 1.0. Life gets even more exciting if I start playing with masking lower order bits.

If I want to mask the 2 low order bits I have
1111 1100 b (binary)
FCh (hex)
252 Decimal

Perhaps I'm unique (after all this is not my day job) but I find it impossible to do arithmetic in dotted decimal.

/tom
Forums » Up and Running » Networking[XP] Need new NIC »
« Any way to set a "Hard" Cap with router?  


Monday, 09-Nov 08:02:25 Terms of Use | Privacy Policy | Hosting by www.nac.net - DSL,Hosting & Co-lo | feedback | contact
over 10 years online! © 1999-2009 dslreports.com.republican-creole
page compression OFF
Most commented news this week
· [156] Cable Uncapper Faces Criminal Charges
· [140] AT&T Sues Verizon Over 3G Ads
· [112] Why Run Fiber When You Can Run Ads That Pretend You Do?
· [109] Comcast Is Simply Getting Huge
· [93] Apple Cooking Up New $30 A Month TV Service?
· [83] Bits Of ACTA Agreement Leaking Out
· [81] Will 'Three Strikes' Come To The United States?
· [78] Verizon To Double Smartphone ETFs?
· [77] Verizon: Droid Tethering Will Cost $30 Extra
· [73] Comcast, NBC Deal Almost Complete
Most people now reading
· [WIN7] Which Services in Win 7 Have You Turned Off? [Microsoft Help]
· Divorce advice... [General Questions]
· 3.x Feral Druid - Bear Tanking Guide [World of Warcraft]
· Framed for child porn 151; by a PC virus [Security]
· Connecting to Google Voice Via SIP [VOIP Tech Chat]
· My cat is reluctant to exercise. [General Questions]
· Is Gear Score now the new requirement to get pug invite? [World of Warcraft]
· [Rant] Brand New 'Jasper' Xbox360 - RRoD Hardware Failure [Rants, Raves, and Praise]
· Windows 7 boot manager editing questions [Microsoft Help]
· plastic box vs. metal box (electrical) [Home Repair & Improvement]