Merge pull request #12 from mcculley/master

Update README.md
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bert hubert 2018-03-31 18:54:24 +02:00 committed by GitHub
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@ -159,7 +159,7 @@ this:
Note that we did not spend time on field Z, this is because it is defined to Note that we did not spend time on field Z, this is because it is defined to
be 0 at all times. This packets does not request recursion. QDCOUNT = 1 be 0 at all times. This packet does not request recursion. QDCOUNT = 1
means there is 1 question. In theory DNS supported several questions in one means there is 1 question. In theory DNS supported several questions in one
message, but this has not been implemented. ANCOUNT, NSCOUNT and ARCOUNT message, but this has not been implemented. ANCOUNT, NSCOUNT and ARCOUNT
are all zero, indicating there as no answers in this question packet. are all zero, indicating there as no answers in this question packet.
@ -190,7 +190,7 @@ Here is the actual question:
* +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ * * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ *
******************************************************** ********************************************************
This consists of the 'www.ietf.org' encoded in DNS wire format (for which This consists of the name 'www.ietf.org' encoded in DNS wire format (for which
see below), followed by a 16 bit type field. For AAAA, which denotes the see below), followed by a 16 bit type field. For AAAA, which denotes the
IPv6 address, this is 28. This is then followed by the 'class' of the IPv6 address, this is 28. This is then followed by the 'class' of the
question. It was originally intended that DNS records would exist in question. It was originally intended that DNS records would exist in
@ -206,7 +206,7 @@ trailing 0 which denotes this is the end.
This format is unusual, but has several highly attractive properties. For This format is unusual, but has several highly attractive properties. For
example, it is binary safe and it needs no escaping. When writing DNS example, it is binary safe and it needs no escaping. When writing DNS
software, it may be tempting to pass DNS names around as "ASCII". This then software, it may be tempting to pass DNS names around as "ASCII". This then
leads to escaping an unescaping code in lots of places. It is highly leads to escaping and unescaping code in lots of places. It is highly
recommended to use the native DNS encoding to store DNS names. This will recommended to use the native DNS encoding to store DNS names. This will
save a lot of pain when processing DNS names with spaces or dots in them. save a lot of pain when processing DNS names with spaces or dots in them.
@ -532,7 +532,7 @@ response with AA=0, indicating that the 'org' servers know they aren't
### Glue records ### Glue records
The astute reader will have spotted a chicken and egg problem here. If The astute reader will have spotted a chicken and egg problem here. If
ns1.ietf.org is the nameserver for ietf.org.. where do we get the IP ns1.ietf.org is the nameserver for ietf.org., where do we get the IP
address of ns1.ietf.org? address of ns1.ietf.org?
To solve this problem, the parent zone can provide a free chicken. In the To solve this problem, the parent zone can provide a free chicken. In the