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Questions tagged [rfc]

An RFC is a "Request For Comments": the form of internet standards from the Internet Engineering Task Force (IETF) until they are made standards. And the usual form of reference to those standards.

An RFC is a "Request For Comments": the form of internet standards from the Internet Engineering Taskforce (IETF) until they are made standards. And the usual form of reference to those standards.

Official Site: http://www.ietf.org/rfc.html

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Are email addresses case sensitive?

I've read that by standard first part of e-mail is case sensitive, however I've tried to send e-mail to name@example.com, Name@example.com and NAME@example.com - it has arrived in each case. How do mail servers handles usernames? Is it possible to…
Stalker
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What is the behavior difference between return-path, reply-to and from?

On our mailing application we are sending emails with the following header: FROM: marketing@customer.com TO: subscriber1@domain1.com Return-PATH: bouncemgmt@ourcompany.com The problem that we are facing is that some email servers will bounce back a…
Geo
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How to overcome root domain CNAME restrictions?

We are hosting many web applications for our customers. As is obvious they want to use their own domains to refer to those applications, usually they want that any user that either type http://www.customer1.example or http://customer1.example goes…
Geo
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RegEx to parse or validate Base64 data

Is it possible to use a RegEx to validate, or sanitize Base64 data? That's the simple question, but the factors that drive this question are what make it difficult. I have a Base64 decoder that can not fully rely on the input data to follow the RFC…
LarryF
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Why do HTTP servers forbid underscores in HTTP header names

I had a problem with a custom HTTP SESSION_ID header not being transfered by nginx proxy. I was told that underscores are prohibited according to the HTTP RFC. Searching, I found that most servers like Apache or nginx define them as illegal in…
white
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The date/time format used in HTTP headers

Which RFC describes the format used for date/time in the modern time HTTP headers, like "Last-Modified" and "If-Modified-Since", and how to generate a date/time string in PHP according to such format? Some sources point to RFC 2822, which, as…
Desmond Hume
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Why is form enctype=multipart/form-data required when uploading a file?

Why is
required when uploading a file to a web-server?
Devi
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What is the maximum length of a DNS name

I saw several mentions that the maximum string length of a DNS name (domain name) is 253 characters. Wikipedia seems to be referring this old blog…
Nicolas Bouvrette
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Can . (period) be part of the path part of an URL?

Is the following URL valid? http://www.example.com/module.php/lib/lib.php According to http://tools.ietf.org/html/rfc1738 section the hpath element of an URL can not contain a '.' (period). There is in the above case a '.' after "module" which is…
Moffe
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When should an asterisk be encoded in an HTTP URL?

According to RFC1738, an asterisk (*) "may be used unencoded within a URL": Thus, only alphanumerics, the special characters "$-_.+!*'(),", and reserved characters used for their reserved purposes may be used unencoded within a URL. However,…
Riley Major
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TCP Sequence Number

I'm trying to understand how the sequence numbers of the TCP header are generated. In some places I read that it is the "index of the first byte in the packet" (link here), on some other sites it is a random 32bit generated number that is then…
m_vdbeek
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Regex for validating multiple E-Mail-Addresses

I got a Regex that validates my mail-addresses like this: ([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?) This works perfectly fine, but only allows one e-mail to be entered. Now I…
SeToY
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Is Oracle's SYS_GUID() UUID RFC 4122 compliant?

I wonder if Oracle's SYS_GUID() function returns a RFC 4122 compliant UUID. For example: SQL> select sys_guid() from dual; SYS_GUID() -------------------------------- A6C1BD5167C366C6E04400144FD25BA0 I know, that SYS_GUID() returns a 16 byte RAW…
nulldevice
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What are RFC's?

I think there are a lot of people out there unaware of RFC's (Request for Comments). I know what they are at a logical level, but can anybody give a good description for a new developer? Also, sharing some resources on how to use and read them would…
Martin York
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Domain names with dots at the end

What is the difference between: domainname and domainname. ? For instance, let's suppose msn.com and msn.com.. I tried both…
Martin Vseticka
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