reviewer #1 wants citation for PTR records and short explanation

[skm-ma-ws1314.git] / sec-dns-extensions.tex

diff --git a/sec-dns-extensions.tex b/sec-dns-extensions.tex
index 86bc75c..e266ba6 100644 (file)
--- a/sec-dns-extensions.tex
+++ b/sec-dns-extensions.tex
@@ -26,7 +26,8 @@ If a host receives a query and knows about the queried resource, it responds to
 querying host with a standard DNS response. The querying host can then simply
 finish and use the result, or wait until other hosts respond to its query. The
 latter is typically the case when a record can have multiple values, as it is
-the case with \code{SRV} and \code{PTR} records.
+the case with \code{SRV} and \code{PTR} records (which will be discussed in the
+next section).
 
 Another feature of Multicast DNS is the reduction of traffic through
 \term{Known-Answer Suppression}. It allows a querying host to specify already
@@ -43,8 +44,10 @@ the network of new services available on a host.
 
 As another recent extension for the Domain Name System, \term{DNS-Based Service
 Discovery (DNS-SD)}~\cite{rfc6763} uses DNS records of types
-SRV~\cite{rfc2782} and PTR in a way that allows hosts to browse
-for services in a domain. This is a two-step process, consisting of
+SRV~\cite{rfc2782} and PTR~\cite{rfc1035} in a way that allows hosts to browse
+for services in a domain. While SRV records specify the location of services on
+a host, PTR records hold a reverse mapping from IP address to host name.
+DNS-SD now relies on a two-step process, consisting of
 \term{Service Instance Enumeration} and \term{Service Instance Resolution}.
 
 \paragraph{1. Service Instance Enumeration} At first, to enumerate the available