diff --git a/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml b/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
index df9a96922c..fd963406d5 100644
--- a/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
+++ b/en_US.ISO8859-1/books/handbook/firewalls/chapter.sgml
@@ -198,7 +198,8 @@
- The Packet Filter (PF) Firewall
+ The OpenBSD Packet Filter (PF) and
+ ALTQ
firewall
@@ -211,10 +212,12 @@
contained PF as an integrated part of the
base system was &os; 5.3 in November 2004.
PF is a complete, fully featured firewall
- that contains ALTQ for bandwidth usage
- management in a way similar to what DUMMYNET provides in
- IPFW. The OpenBSD project does an
- outstanding job of maintaining the PF users' guide that it will
+ that has optional support for ALTQ (Alternate
+ Queuing). ALTQ provides Quality of Service
+ (QoS) bandwidth shaping that allows
+ guaranteeing bandwidth to different services based on filtering
+ rules. The OpenBSD Project does an
+ outstanding job of maintaining the PF User's Guide that it will
not be made part of this handbook firewall section as that would
just be duplicated effort.
@@ -358,6 +361,63 @@ pflog_flags="" # additional flags for pflogd startupgateway_enable="YES" # Enable as LAN gateway
+
+
+ Enabling ALTQ
+
+ ALTQ is only available by compiling the
+ options into the &os; Kernel. ALTQ is not
+ supported by all of the available network card drivers. Please
+ see the &man.altq.4; manual page for a list of drivers that are
+ supported in your release of &os;. The following options will
+ enable ALTQ and add additional functionality.
+
+
+ options ALTQ
+options ALTQ_CBQ # Class Bases Queuing (CBQ)
+options ALTQ_RED # Random Early Detection (RED)
+options ALTQ_RIO # RED In/Out
+options ALTQ_HFSC # Hierarchical Packet Scheduler (HFSC)
+options ALTQ_PRIQ # Priority Queuing (PRIQ)
+options ALTQ_NOPCC # Required for SMP build
+
+ options ALTQ enables the
+ ALTQ framework.
+
+ options ALTQ_CBQ enables Class Based
+ Queuing (CBQ). CBQ
+ allows you to divide a connection's bandwidth into different
+ classes or queues to prioritize traffic based on filter
+ rules.
+
+ options ALTQ_RED enables Random Early
+ Detection (RED). RED is
+ used to avoid network congestion. RED does
+ this by measuring the length of the queue and comparing it to
+ the minimum and maximum thresholds for the queue. If the
+ queue is over the maximum all new packets will be dropped.
+ True to its name, RED drops packets from
+ different connections randomly.
+
+ options ALTQ_RIO enables Random Early
+ Detection In and Out.
+
+ options ALTQ_HFSC enables the
+ Hierarchical Fair Service Curve Packet Scheduler. For more
+ information about HFSC see: .
+
+
+ options ALTQ_PRIQ enables Priority
+ Queuing (PRIQ). PRIQ
+ will always pass traffic that is in a higher queue
+ first.
+
+ options ALTQ_NOPCC enables
+ SMP support for ALTQ.
+ This option is required on SMP
+ systems.
+