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diff --git a/qos/abstract b/qos/abstract
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+Quality of Service in IP Networks
+
+IP networks were designed some 25 years ago.  Networks based on TCP/IP are
+widely deployed, as organization-local Intranets as well as in the Internet
+itself.  The usage patterns of those networks change.  Especially new 
+technologies like voice-over-IP as well as streaming multimedia applications
+have different requirements on the underlying network infrastructure than 
+bulk data transfers like ftp/www or interactive traffic like telnet/ssh.
+
+Organizations usually run a mixture of different services on their Internet
+uplinks or on their organization-internal wide area networks.  Bandwidth is 
+usually a limited ressource, so everybody wants to divide bandwidth between
+different services according to his specific needs. 
+
+Linux always had a very strong focus on network functionality and has
+sophisticated means for bandwidth control / QoS since Kernel 2.2.
+
+The presentation is organized in the following parts:
+	Basics of QoS in IP networks
+	How can Linux help with QoS
+	Sample scenarios of Linux-based QoS solutions
+	Overview about advanced conecpts (DiffServ, IntServ, RSVP, ...)
+	
diff --git a/qos/ip-qos.mgp b/qos/ip-qos.mgp
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+%include "cnc-style.mgp"
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+%nodefault
+%pcache 1 1 0 1
+%size 7, font "standard", fore "white", vgap 20, back "black"
+%bimage "fundo-cnc.png" 1024x768
+
+%center
+%size 7
+
+
+Quality of Service in IP Networks
+
+%center
+%size 4
+by
+
+Harald Welte <laforge@conectiva.com>
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Contents
+
+	Definition of QoS
+
+	Why QoS
+
+	IP Networks are not designed for QoS
+
+	How to do the impossible
+
+	What can Linux based systems help
+
+	Advanced Concepts (DiffServ, IntServ, RSVP, ...)
+
+	References / Further Reading
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Definiton of QoS
+
+	Provide Service Differentiation
+
+	Performance Assurance by
+
+		Bandwitdh guarantees
+			for streaming multimedia traffic
+			priorizing certain important applications
+
+		Latency guarantees
+			for voice over IP
+			for interactive character-oriented applications (ssh,telnet)
+
+		Packet-loss guarantees
+			for unreliable layer-4 protocols
+			to avoid retransmits
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page 
+QoS in IP Networks
+Why QoS
+
+
+	Decide how and who available bandwidth is devided
+
+	Limit available bandwidth for certain users / applications
+
+	Guarantee bandwidth for certain users / applications
+
+	Divide bandwidth more equally between users / applications
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page 
+QoS in IP Networks
+IP networks not designed for QoS
+
+
+Properties of IP-based networks:
+
+	offer a "best-effort" service
+
+	make NO guarantees about 
+		bandwidth
+		latency
+		packet loss
+
+	provide a non-reliable packet transport
+
+Conclusion: IP networks are not suitable for QoS
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+How to do the Impossible
+
+%size 4
+
+As IP Networks including Hardware (Routers, ...) are widely deployed, all QoS efforts have to layer on top of the existing technology.
+
+	There's no real solution to control latency
+		latency widely dependent on routing, which may be dynamic
+
+	There's no real solution to control packet loss
+		packet loss may occurr on any intermediate router
+
+	But we can control bandwidth usage!
+		The sender can limit bandwidth for outgoing streams
+		Intermediate routers BEFORE a bottleneck can control bandwidth usage
+
+%size 5
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+What can Linux systems do?
+
+	Bandwidth limiting at the sender application
+		not many applications support it
+		server often out of control (on Internet, ...)
+		server doesn't know what's between him and the client
+
+	Bandwidth control on intermediate router before bottleneck
+		Ideal case because this is where packet loss would occurr
+		Sophisticated queue scheduling on the outgoing queue
+		Variety of different queue scheduling algorithms
+
+	Flow throttling at the Receiver
+		Worst case, because influence is limited
+		Theoretically possible for TCP, no implementation yet.
+		Ingress qdisc might help
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Bandwidth limiting at server
+
+	Some Internet Servers support bandwidth limiting
+
+		ProFTPd (builtin support)
+
+		Apache (using contributed mod_bandwidth)
+
+
+	Using those features it is easy to limit
+
+		maximum bandwidth used per connection 
+
+		maximum bandwidth used per client (IP/network)
+
+		maximum bandwidth used by one virtual host (webserver/ftpserver)
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Router before bottleneck
+
+%size 4
+
+The router receives more packets on his incoming interface(s) than it can send out on the outgoing interface. It has to build a queue of packets (usually a FIFO one) and starts dropping packets as soon as the queue is full
+
+%image "qos-1.png" 0 100 30
+
+The idea is to change this queue, thus decide
+	which packets get enqueued in which order
+	how many packets get queued
+	which packets get dropped in case of a filling queue
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+The Linux 2.2 / 2.4 Solution
+
+	Packet Scheduling algorithms in the Kernel
+		CBQ - Class Based Queue
+		RED - Random Early Drop
+		SFQ - Stochastic Fairness Queueing
+		TEQL - True Link Equalizer
+		TBF - Token Bucket Filter
+
+	tc command of iproute2 package for configuration
+		almost no documentation
+		very few examples on the internet
+
+	Packet Classification
+		tc builtin classes (route, u23, ...)
+		all iptables/netfilter matches by using fwmark
+
+Conclusion: Linux is the best suited general-purpose operating system for QoS, but almost nobody is using it because lack of knowledge.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Available queuing algorithms
+
+	CBQ - Class Based Queue
+		hierarchical bandwidth classes
+		used as basis in almost all cases
+	TBF - Token Bucket Filter
+		really accurate algorithm
+		uses a lot of CPU
+		not possible for high bandwidth links (>1MBit)
+	SFQ - Stochastic Fairness Queueing
+		less accurate algorithm
+		tries to distinguish between individual streams
+		does round robin between those streams
+	TEQL - True Link Equalizer
+		allows to 'bundle' interfaces
+	RED - Random Early Detect / Drop
+		simulates congested link by statistic packet dropping
+		uses almost no CPU
+		recommended for high-bandwidth backbones
+	others (WRR, TCINDEX, DSMARK, ..)
+		WRR not officially included in kernel, similar to CBQ	
+		others mostly used for DiffServ
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+The big picture
+
+Overview of the a packet's journey
+
+%size 3
+%font "typewriter"
+    Incoming Packets 
+%size 3
+%font "typewriter"
+           |
+%size 3
+%font "typewriter"
+           V
+%size 3
+%font "typewriter"
+ Packet Classification          classify
+%size 3
+%font "typewriter"
+  (ipchains/iptables)           set nfmark
+%size 3
+%font "typewriter"
+           |
+%size 3
+%font "typewriter"
+           V
+%size 3
+%font "typewriter"
+    Routing decision
+%size 3
+%font "typewriter"
+           |
+%size 3
+%font "typewriter"
+           V
+%size 3
+%font "typewriter"
+       TC filter                select classes based on nfmark
+%size 3
+%font "typewriter"
+      /    |    \ 
+%size 3
+%font "typewriter"
+     /     |     \ 
+%size 3
+%font "typewriter"
+    /      |      \ 
+%size 3
+%font "typewriter"
+Different Bandwidth classes     bandwidth classes (CBQ)
+%size 3
+%font "typewriter"
+    \      |      /
+%size 3
+%font "typewriter"
+     \     |     /
+%size 3
+%font "typewriter"
+      \    |    /
+%size 3
+%font "typewriter"
+       Enqueuing                output queue discipline
+%size 3
+%font "typewriter"
+           |
+%size 3
+%font "typewriter"
+           V
+%size 3
+%font "typewriter"
+    Outgoing packets
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Example scenario usin CBQ
+
+%size 4
+Let's assume we have a link with 10 MBit maximum available bandwidth.
+We offer two major services to the outside world: Anonymous FTP and a Webserver offering important Information. 
+
+FTP Bulk data transfers are using up almost all available bandwidth, thus slowing down accesses to our website :(
+
+We want to have FTP transfers use up to 8MBit and reserve 2MBit for WWW.
+
+Implementation uses CBQ for bandwidth divisions.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Example scenario
+
+%size 3
+	attach a CBQ to the device 
+%size 3
+%font "typewriter"
+tc qdisc add dev eth0 root handle 10: cbq 
+   bandwidth 10Mbit avpkt 1000
+
+%size 3
+%font "standard"
+	create CBQ classes
+%size 3
+%font "typewriter"
+tc class add dev eth0 parent 10:0 classid 10:1 cbq 
+   bandwidth 10MBit rate 10MBit allot 1514 
+   weight 1Mbit prio 8 maxburst 20 avpkt 1000
+
+tc class add dev eth0 parent 10:1 classid 10:100 cbq 
+   bandwidth 10MBit rate 8MBit allot 1514 
+   weight 800kbit prio 5 maxburst 20 avpkt 1000 bounded
+
+tc class add dev eth0 parent 10:1 classid 10:200 cbq 
+   bandwidth 10MBit rate 2MBit allot 1514 
+   weight 200kbit prio 5 maxburst 20 avpkt 1000 bounded
+
+%size 3
+%font "standard"
+	add filter rules
+%size 3
+%font "typewriter"
+tc filter add dev eth0 parent 10:1 protocol ip handle 6 fw classid 10:100
+
+iptables -t mangle -A PREROUTING -j MARK -p tcp --sport 20 --set-mark 6
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Further optimization
+
+%size 4
+Now we have achieved bandwidth division between two services. 
+
+Within one service, however, one individual user with a high bandwith link can still use up most of our bandwidth, slowing down other user.
+
+We can improve this behaviour of changing the scheduling algorithm from it's default (fifo)
+
+%size 3
+%font "typewriter"
+tc qdisc add dev eth0 parent 10:100 sfq quantum 1514b perturb 15
+tc qdisc add dev eth0 parent 10:200 sfq quantum 1514b perturb 15
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+QoS in IP Networks
+Further reading / Links
+
+	Bandwidth limiting on Servers
+		ProFTPd 
+			http://www.proftpd.net/
+		Apache mod_bandwidth / mod_bwshare
+			ftp://ftp.cohprog.com/pub/apache/module/mod_bandwidth.c
+			http://www.topology.org/src/bwshare/
+
+	Queue scheduling 
+		Advanced Routing HOWTO
+			http://www.ds9a.nl/2.4Routing/
+		Linux QoS HOWTO
+			http://www.ittc.ukans.edu/~rsarav/howto/
+		iproute2+tc
+
+	This presentation
+		Authors Homepage
+			http://www.gnumonks.org/
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