1. PMIPv6 Implementation in NS HyonYoung Choi (commani@gmail.com)
NS Tutorial
PMIPv6 Implementation in NS
HyonYoung Choi

2. 목차
NS 기초
PMIPv6 Implementation

3. NS 기초

4. Tcl와 C++의 연관관계 Tcl Object와 C++ Object의 매핑
TclClass가 Tcl에서 C++ object를 만들 수 있도록 해줌
TclClass의 생성자 인수가 Tcl에서 사용가능한 Object 이름
set mag [new Agent/PMIPv6/MAG]
static class MAGAgentClass : public TclClass {
public:
MAGAgentClass() : TclClass("Agent/PMIPv6/MAG") {}
TclObject* create(int, const char*const*) {
return (new MAGAgent()); }
} class_magagent;
class MAGAgent : public PMIPv6Agent {
public:
MAGAgent(); …… };

5. NS의 함수(1/4) 함수의 정의 Tcl: instproc를 사용하여 정의
C++: TclObject class의 command 함수 overriding후 if- else-if로 string match
Classifier/Addr/PMIPv6Dest instproc install {dst target} {
$self instvar classifier_
$classifier_ install $dst $target }
int MAGAgent::command(int argc, const char*const* argv) {
if(argc==3) {
if(strcmp(argv[1], "new-mn") == 0) { ……
return TCL_OK;
} else if(strcmp(argv[1], "set-lmaa") == 0) {
return (PMIPv6Agent::command(argc, argv)); }

6. NS의 함수(2/4) Tcl 함수와 C++ 함수의 장단점 장점 단점 Tcl 함수 Type이 없어 변수처리가 쉽다
배열, 리스트, 타이머 처리가 용이하다
변수 값에 의한 버그 발생
C++보다 실행속도가 늦다
C++ 함수
Object 접근이 쉽다
Tcl보다 실행속도가 빠르다
Object 상호참조로 구조가 복잡해질 수 있다.

7. NS의 함수(3/4) Tcl 함수와 C++ 함수의 상호접근 함수 호출의 우선순위: Tcl > C++
Tcl의 함수에서 찾은 뒤 없으면 C++의 command 함수 호출
Tcl과 C++에 같은 이름의 함수가 있는 경우
Tcl의 함수 호출: 일반적인 함수 호출
C++의 함수 호출: 함수이름 앞에 “cmd”를 추가
Classifier/Addr/PMIPv6Dest instproc clear { dst } {
$self instvar classifier_
$classifier_ clear $dst }
Classifier/Addr/PMIPv6Dest instproc clear-by-dest { addr } {
$self cmd clear $addr

8. NS의 함수(4/4) Tcl 함수와 C++ 함수의 상호접근 (cont’d) C++에서 Tcl 함수의 결과값 얻기
Tcl::eval, Tcl::evalf 함수 사용
C++에서 Tcl 함수의 결과값 얻기
Tcl::result 함수 사용
C++ 함수에서 Tcl로 결과값 반환(return)
Tcl::resultf 함수 사용
Tcl& tcl = Tcl::instance();
tcl.evalf("%s setup-route %ld %ld", name(), bule->mn_prefix(), bule->lmaa());
tcl.evalf ("%s getRXThresh",netif_->name());
RXThreshold_ = atof (tcl.result());
if (strcmp(argv[1], "ifq") == 0) {
tcl.resultf("%s", ifq_->name());
return (TCL_OK); }

9. 새로운 packet type 만들기(1/4) 1. Packet 헤더 작성
offset_, offset(), access(Packet *p) 작성 (필수)
HDR_XXX define 작성 (옵션)
offset_이 static이므로 C++소스 파일에 선언
#define HDR_PMIPv6((p) ((struct hdr_pmipv6*)(p)->access(hdr_pmipv6::offset_))
struct hdr_pmipv6 {
……(패킷 헤더의 필드들)
static int offset_;
inline static int& offset() { return offset_; }
inline static hdr_pmipv6* access(Packet* p) {
return (hdr_pmipv6*) p->access(offset_); } };
int hdr_pmipv6::offset_;

10. 새로운 packet type 만들기(2/4) 2. PacketHeaderClass 작성
Packet Manager용 class 작성
3. ns-packet.tcl 수정 (ns-2.29/tcl/lib/)
PacketHeaderClass 생성자의 이름과 일치해야 함
static class PMIPv6HeaderClass : public PacketHeaderClass {
public:
PMIPv6HeaderClass() : PacketHeaderClass("PacketHeader/PMIPv6", sizeof(hdr_pmipv6)) {
bind_offset(&hdr_pmipv6::offset_); }
} class_pmipv6hdr;
foreach prot { ……
PMIPv6
} {
add-packet-header $prot }

11. 새로운 packet type 만들기(3/4) 4. packet.h 수정 (ns-2.29/common/)
enum packet_t의 PT_NTYPE 전에 넣음
name_ 작성: trace에 표시되는 패킷 type
enum packet_t { ……
//PMIP6: type
PT_PBU,
PT_PBACK,
PT_NTYPE // This MUST be the LAST one };
p_info() { ……
name_[PT_PBU]="pbu";
name_[PT_PBACK]="pba";
name_[PT_NTYPE]= "undefined"; }

12. 새로운 packet type 만들기(4/4) 패킷 생성 allockpkt 함수 사용 hdr_cmn 정보 반드시 채울 것
size: 실제 전송되는 총 패킷 크기
ptype: packet type
Packet *p = allocpkt();
hdr_cmn *hdrc = HDR_CMN(p);
hdr_ip *iph = HDR_IP(p);
hdr_pmipv6 *h = HDR_PMIPv6(p);
hdrc->size() = IPv6_HEADER_SIZE;
hdrc->ptype() = PT_PBU;
hdrc->size() += PBU_SIZE;
iph->saddr() = proxy_coa;
iph->sport() = port(); ……

13. List 관리 – Tcl (1/2) 배열로 처리 (index에 문자도 가능) 중복처리를 쉽게 할 수 있음 간단한 형태만 가능
덮어 쓰는 경우는 바로 추가
이미 존재하면 에러인 경우는 이미 있는지 검사
info exists 사용
Node instproc listadd {index value} {
$self instvar List_
if { ! [info exists List_($index)] || $List_($index)==“”} {
set List_($index) $value }

14. List 관리 – Tcl (2/2) 2. List 제거 존재 하는 경우 “”로 만들거나 unset
Node instproc listdel {index} {
$self instvar List_
if { [info exists List_($index)] && $List_($index)!=“”} {
set List_($index) “”
unset List_($index) }

15. List 관리 - C++ (1/2) List 관련 매크로 활용 1. LIST_HEAD 정의
2. 리스트 각 entry 내용 정의
insert_entry. next_entry, remove_entry, link 정의
class BULEntry;
LIST_HEAD(bulEntry, BULEntry);
class BULEntry { ……
public:
inline void insert_entry(struct bulEntry *head) { LIST_INSERT_HEAD(head, this, link); }
BULEntry* next_entry(void) const { return link.le_next; }
inline void remove_entry() { LIST_REMOVE(this, link); }
protected:
LIST_ENTRY(BULEntry) link; };

16. List 관리 - C++ (2/2) 3. List 사용 List 변수 정의 List에 추가 List에서 찾기
class MAGAgent : public PMIPv6Agent { ……
struct bulEntry bul_list_;
void MAGAgent::process_new_mn(int32_t mn_id) { ……
bule->insert_entry(&bul_list_);
BULEntry *MAGAgent::find_bule(int32_t mn_id) {
for(BULEntry *bule=bul_list_.lh_first; bule; bule=bule->next_entry()) {
if(bule->mn_id() == mn_id)
return bule; }
return NULL;

17. Timer 관리 - Tcl ns simulator의 at 함수 활용 1. timeout시 실행될 함수 정의
Node instproc record {} {
set ns [Simulator instance]
…….. }
Node instproc start { mnaddr } {
$self instvar RTimer_
set ns [Simulator instance]
set now [$ns now]
if {![info exists RTimer_($mnaddr)] ||
$RTimer_($mnaddr) == ""} {
$ns at [expr $now + 1.0] “$self record” }
Node instproc stop { mnaddr } {
$self instvar RTimer_
set ns [Simulator instance]
if {[info exists RTimer_($mnaddr)] &&
$RTimer_($mnaddr) != ""} {
$ns cancel $RTimer_($mnaddr)
set Rtimer_($mnaddr) “” }

18. Timer 관리 – C++ (1/2) TimerHandler를 사용하여 구현 1. TimerHandler를 상속한 클래스 정의
생성자에 호출할 정보를 넣도록 작성
expire 함수를 반드시 overriding
class BindingTimer : public TimerHandler {
public:
BindingTimer(PMIPv6Agent *pagent, void *data): TimerHandler() {
pagent_ = pagent;
data_ = data; }
protected:
PMIPv6Agent *pagent_;
void *data_;
void expire(Event *); };

19. Timer 관리 – C++ (2/2) 2. expire 함수 정의 3. timer 시작과 중단 하기
생성자로 받은 정보를 사용해 원하는 작업 수행
3. timer 시작과 중단 하기
resched 함수와 cancel 함수 사용
void BindingTimer::expire(Event *) {
pagent_->BindingTimeout(data_); }
bule->BULTimer_.resched(1.0);
bule->BULTimer_.cancel ();

20. PMIPv6 Implementation

21. PMIPv6 Objects (1/2) PacketHeader/PMIPv6 (struct hdr_pmipv6)
PBU, PBACK 패킷을 위한 헤더
PacketHeader/IP6Encap (struct hdr_ip6encap)
IPv6-in-IPv6 패킷을 위한 헤더
Agent/PMIPv6 (class PMIPv6Agent)
LMA와 MAG의 상위 클래스
Agent/PMIPv6/LMA (class LMAAgent)
LMA Agent
Agent/PMIPv6/MAG (class MAGAgent)
MAG Agent

22. PMIPv6 Objects (2/2) PMIPv6Encapsulator (class PMIPv6Encapsulator)
IPv6-in-IPv6 Encapsulator
Classifier/Addr/PMIPv6Src (class PMIPv6Src)
Source address based routing
Classifier/Addr/PMIPv6Dest (class PMIPv6Dest)
Destination address routing
Classifier/Addr/PMIPv6Decapsulator (class PMIPv6Decapsulator)
IPv6-in-IPv6 Decapsulator

23. PMIPv6 example script

24. General Initialization
Hierarchical routing
MN 패킷이 LMA로 routing 되도록 하기 위함
Wireless configuration
# set up for hierarchical routing (needed for routing over a basestation)
$ns node-config -addressType hierarchical
AddrParams set domain_num_ ;# domain number
AddrParams set cluster_num_ { }
AddrParams set nodes_num_ { }
# Parameter for wireless nodes
set opt(chan) Channel/WirelessChannel ;# channel type
set opt(prop) Propagation/TwoRayGround ;# radio-propagation model
set opt(netif) Phy/WirelessPhy ;# network interface type
set opt(mac) Mac/802_ ;# MAC type
set opt(ifq) Queue/DropTail/PriQueue ;# interface queue type
set opt(ll) LL ;# link layer type
set opt(ant) Antenna/OmniAntenna ;# antenna model
set opt(ifqlen) ;# max packet in ifq
set opt(adhocRouting) DSDV ;# routing protocol

25. PMIPv6 Initialization (1/8)
LMA
LMA Node 생성 후 install-lma 함수 호출
주의사항: duplex-link 호출 전에 install-lma 호출
set lma [$ns node 1.0.0]
#attach Agent/PMIPv6/LMA to the LMA
set lma_pm [$lma install-lma]
#BE CAREFUL!. PMIPv6 agent must be installed before connecting link(duplex-link)
$ns duplex-link $lma $router 100Mb $opt(dfLinkDelay) DropTail

26. PMIPv6 Initialization (2/8)
LMA (cont’d)
install-lma 함수

27. PMIPv6 Initialization (3/8)
install-lma 함수
Node instproc install-lma {} {
$self instvar classifier_ decap_ dmux_ agents_
$self instvar pmip6_agent_
$self instvar dst_classifier_ old_classifier_
#attach pmip6 agent
set lma [new Agent/PMIPv6/LMA]
$self attach $lma [$lma set default_port_]
set pmip6_agent_ $lma
#attach dest classifier
set old_classifier_ $classifier_
set dst_classifier_ [new Classifier/Addr/PMIPv6Dest]
$dst_classifier_ set mask_ 0xffffffff
$dst_classifier_ set shift_ 0
$dst_classifier_ defaulttarget $old_classifier_

28. PMIPv6 Initialization (4/8)
install-lma 함수 (cont’d)
set nodetype [[Simulator instance] get-nodetype]
$self insert-entry [$self get-module $nodetype] $dst_classifier_
$dst_classifier_ install-by-dest 0 $old_classifier_
#attach decapsulator
set decap_ [new Classifier/Addr/PMIPv6Decapsulator]
$decap_ set mask_ 0xffffffff
$decap_ set shift_ 0
$decap_ defaulttarget $dst_classifier_
lappend $agents_ $decap_
$dmux_ install [Simulator set PMIPv6_TUNNEL_PORT] $decap_
return $lma }

29. PMIPv6 Initialization (5/8)
MAG
NIST settings: bssid, channel, beacon 설정
install-mag 호출
set-lmaa 호출: LMA Address 지정
MAC에 trigger를 위한 설정
set mag1 [$ns node 3.0.0]
$mag1 random-motion 0
$mag1 set X_ 100.0
$mag1 set Y_ 200.0
$mag1 set Z_ 0.0
#NIST settings
set mag1_mac [$mag1 getMac 0]
set mag1_addr [$mag1_mac id]
$mag1_mac bss_id $mag1_addr
$mag1_mac set-channel 1
$mag1_mac enable-beacon
#install PMIPv6/MAG agent to the MAG1
set mag1_pm [$mag1 install-mag]
set lmaa [$lma node-addr]
$mag1_pm set-lmaa [AddrParams addr2id $lmaa]
#setup MAC to support MN ATTACH Event
$mag1_mac set use_pmip6_ext_ 1
$mag1_mac pmip6-agent $mag1_pm
$ns duplex-link $mag1 $router 100Mb $opt(dfLinkDelay) DropTail

30. PMIPv6 Initialization (6/8)
MAG (cont’d)

31. PMIPv6 Initialization (7/8)
install-mag 함수
Node instproc install-mag {} {
$self instvar classifier_ dmux_ agents_ ll_
$self instvar pmip6_agent_
$self instvar src_classifier_ old_classifier_
$self instvar decap_
set mag [new Agent/PMIPv6/MAG]
$self attach $mag [$mag set default_port_]
set pmip6_agent_ $mag
#attach src classifier
set old_classifier_ $classifier_
set src_classifier_ [new Classifier/Addr/PMIPv6Src]
$src_classifier_ set mask_ 0xffffffff
$src_classifier_ set shift_ 0
$src_classifier_ defaulttarget $old_classifier_

32. PMIPv6 Initialization (8/8)
install-mag 함수 (cont’d)
set nodetype [[Simulator instance] get-nodetype]
$self insert-entry [$self get-module $nodetype] $src_classifier_
$src_classifier_ install-by-src 0 $old_classifier_
#attach decap_
set decap_ [new Classifier/Addr/PMIPv6Decapsulator]
$decap_ set mask_ 0xffffffff
$decap_ set shift_ 0
lappend $agents_ $decap_
$dmux_ install [Simulator set PMIPv6_TUNNEL_PORT] $decap_
# LL points previous hier_classifier as up-target
# we should change this to our classifier
if {[info exists ll_(0)] && $ll_(0) != ""} {
$ll_(0) up-target $src_classifier_ }
return $mag

33. Binding Update Process (1/3)
Sending PBU
Mac802_11
MAGAgent
PMIPv6Agent
new-mn/TCL
command()
process_new_mn()
-find_bule
send_pbu()
create_pbu()
send()

34. Binding Update Process (2/3)
Receiving PBU/Sending PBACK
PMIPv6Agent
LMAAgent
recv()
process_packet()
process_pbu()
-find_bce()
setup_route()
setup-route/TCL
-get-pmip6-encap/TCL
send_pback()
create_pback()
send()

35. Binding Update Process (3/3)
Receiving PBACK
PMIPv6Agent
MAGAgent
recv()
process_packet()
process_pback()
-find_bule()
setup_route()
bule_state: BUL_S_SETUP
setup-route/TCL
-get-pmip6-encap/TCL
clear_route()
bule_state: BUL_S_DELETE
clear-route/TCL

36. Data Process (1/2) LMA  MAG PMIPv6Dest PMIPv6Encapsulator
PMIPv6Decapsulator
recv()
classify()
recv()
target_->recv()
recv()
find()
link->recv()

37. Data Process (2/2) MAG  LMA PMIPv6Src PMIPv6Encapsulator
PMIPv6Decapsulator
recv()
classify()
recv()
target_->recv()
recv()
find()
link->recv()

38. 802.11 MAC Operation (1/5) 802.11 MAC에서 Layer 2 Trigger 발생 Mac802_11
MAGAgent
PMIPv6Agent
new-mn/TCL
command()
process_new_mn()
-find_bule
send_pbu()
create_pbu()
send()

39. 802.11 MAC Operation (2/5) 802.11 MAC 수정
class Mac802_11 (ns-2.29/mac/mac-802_11.h)
use_pmip6_ext_: PMIPv6용 L2 trigger 사용
pmip6_agent_: L2 trigger를 전달할 PMIPv6 agent
pmip6-agent 함수 추가
class Mac802_11 : public Mac { ……
//PMIPv6
int use_pmip6_ext_;
Agent* pmip6_agent_;
//End PMIPv6
int Mac802_11::command(int argc, const char*const* argv) { ……
else if (strcmp(argv[1], "pmip6-agent") == 0) {
if(use_pmip6_ext_==0) return TCL_ERROR;
pmip6_agent_ = (Agent *)TclObject::lookup(argv[2]);
return TCL_OK; }

40. 802.11 MAC Operation (3/5) 802.11 MAC 수정 (cont’d)
MAC에서 AP address 적용 버그 수정
Link 가 끊어졌을 때 자동으로 스캔하도록 수정
inline int Mac802_11::hdr_dst(char* hdr, int dst ) { ……
//PMIPv6
if(dst != bss_id_)
STORE4BYTE(&bss_id_, (dh->dh_3a));
//end PMIPv6
void Mac802_11::link_disconnect (link_down_reason_t reason) { ……
//PMIPv6
if(!mih_) {
//If disconnected, it automatically starts scanning
Tcl& tcl = Tcl::instance();
tcl.evalf ("%s autoscan", name()); }
//PMIPv6 end

41. 802.11 MAC Operation (4/5) 802.11 MAC 수정 (cont’d) AP를 발견하면 바로 연결되도록 수정
void Mac802_11::nextScan () { ……
//PMIPv6
if(!mih_) {
BSSDescription *n;
n=scan_status_.resp->bssDesc_head.lh_first;
//store structure scan bssid/channel Vincent Gauthier
channelIDAfterScan_[n->bss_id()] = n->channel();
link_connect(n->bss_id()); }
//PMIPv6 end

42. 802.11 MAC Operation (5/5) Layer 2 Trigger 발생 AssocRes 메시지가 도착하면 시작
PMIPv6 agent의 new-mn 함수 호출
void Mac802_11::recvACK(Packet *p) { ……
//PMIPv6
if(use_pmip6_ext_) {
if(pmip6_agent_) {
Tcl& tcl = Tcl::instance();
tcl.evalf("%s new-mn %d", pmip6_agent_->name(), n->id()); }
//end PMIPv6

43. MAG Operation #1 (1/5) MAG에서 L2 Trigger 처리 후 PBU 전송 Mac802_11 MAGAgent
PMIPv6Agent
new-mn/TCL
command()
process_new_mn()
-find_bule
send_pbu()
create_pbu()
send()

44. MAG Operation #1 (1/4) new-mn 함수 이후 process_new_mn 호출
Binding Update List 처리
BUL entry (bule)
PBU retransmission timer
마지막 PBU 저장 (pktPBU_)
int MAGAgent::command(int argc, const char*const* argv) { ……
else if(argc==3) {
if(strcmp(argv[1], "new-mn") == 0) {
uint32_t id;
id = atoi(argv[2]);
process_new_mn(id);
return TCL_OK; }

45. MAG Operation #1 (2/4) process_new_mn 함수 (cont’d) else {
void MAGAgent::process_new_mn(int32_t mn_id) {
BULEntry *bule;
bule = find_bule(mn_id);
if(!bule) {
bule = create_bule(mn_id);
bule->lmaa() = lma_addr_;
bule->proxy_coa() = addr();
bule->lifetime() = binding_lifetime_;
bule->insert_entry(&bul_list_); }
else {
bule->BULTimer_.cancel();
if(bule->pktPBU_) {
Packet::free(bule->pktPBU_);
bule->pktPBU_ = 0; }
bule->set_state(BUL_S_SETUP);
bule->retry_count_ = 0;
send_pbu(bule);

46. MAG Operation #1 (3/4) send_pbu 함수 PMIPv6Agent의 create_pbu 함수로 PBU 생성
bule에 생성된 PBU를 저장하고 복사본 전송
Retransmission timer 설정
void MAGAgent::send_pbu(BULEntry *bule) {
if(!bule->pktPBU_) {
bule->pktPBU_ =
create_pbu(bule->lmaa(), bule->mn_id(), bule->lifetime(), bule->proxy_coa()); }
send(bule->pktPBU_->copy(), 0);
//FIXME: adjust retransmit timeout (Random backoff??)
bule->BULTimer_.resched(1.0);

47. MAG Operation #1 (4/4) create_pbu 함수 Packet *PMIPv6Agent::create_pbu(
int32_t dst, int32_t mn_id,
uint32_t lifetime, int32_t proxy_coa) {
Packet *p = allocpkt();
hdr_cmn *hdrc = HDR_CMN(p);
hdr_ip *iph = HDR_IP(p);
hdr_pmipv6 *h = HDR_PMIPv6(p);
hdrc->size() = IPv6_HEADER_SIZE;
hdrc->ptype() = PT_PBU;
hdrc->size() += PBU_SIZE;
iph->saddr() = proxy_coa;
iph->sport() = port();
iph->daddr() = dst;
iph->dport() = port();
h->H() = 1;
h->A() = 1;
h->P() = 1;
h->type() = PBU;
h->seqno() = 0;
h->lifetime() = lifetime;
h->mn_id() = mn_id;
h->coa() = proxy_coa;
h->haddr() = -1;
h->status() = 0;
return p; }

48. LMA Operation (1/7) Receiving PBU/Sending PBACK PMIPv6Agent LMAAgent
recv()
process_packet()
process_pbu()
-find_bce()
setup_route()
setup-route/TCL
-get-pmip6-encap/TCL
send_pback()
create_pback()
send()

49. LMA Operation (2/7) PMIPv6Agent의 recv 함수
PBU의 IP헤더 dest port에 따라 recv함수 호출됨
void PMIPv6Agent::recv(Packet* p, Handler *) {
hdr_cmn *hdrc = HDR_CMN(p);
int ptype;
ptype = hdrc->ptype();
if((ptype==PT_PBU && strcmp(node_info_, "LMA")==0) ||
(ptype==PT_PBACK && strcmp(node_info_, "MAG")==0)) {
process_packet(p); }
else {
fprintf(stderr, "%s received packet with wrong type %d\n", node_info_, ptype);
Packet::free(p);

50. LMA Operation (3/7) process_packet 함수
virtual이며, LMAAgent와 MAGAgent에서 override함
process_pbu 함수 호출
process_pbu 함수
Binding cache 찾기, lifetime처리
Lifetime에 따라 Routing 설정
PBACK 보내기
void LMAAgent::process_packet(Packet *p) {
hdr_cmn *ch = HDR_CMN(p);
if(ch->ptype() == PT_PBU) {
process_pbu(p); }
Packet::free(p); }

51. LMA Operation (4/7) process_pbu 함수(cont’d)
void LMAAgent::process_pbu(Packet *p) {
hdr_ip *iph = hdr_ip::access(p);
hdr_pmipv6 *h = hdr_pmipv6::access(p);
int mn_id, mnaddr;
BCacheEntry *bce;
mn_id = h->mn_id();
bce = find_bce(mn_id);
if(!bce) {
if(h->lifetime()==0) {
send_pback(p, 0); return; }
if((mnaddr=find_mn_prefix(mn_id))==-1) {
send_pback(p, 1); return; }
bce = create_bce(mn_id);
bce->proxy_coa() = iph->saddr();
bce->mn_prefix() = mnaddr;
bce->insert_entry(&bcache_list_); }
if(h->lifetime()==0 &&
bce->proxy_coa()!=iph->saddr()) {
send_pback(p, 0); return; }
bce->lifetime() = h->lifetime();
if(bce->lifetime()>0) setup_route(bce);
else clear_route(bce);
send_pback(bce, 0);
bce->BCacheTimer_.resched(
(double)bce->lifetime()); }

52. LMA Operation (5/7) setup_route 함수: tcl의 setup-route 함수 호출
MN의 주소의 패킷이 PMIPv6Encapsulator로 전달되도 록 PMIPv6Dest classifier에 등록
Agent/PMIPv6/LMA instproc setup-route { mnaddr te } {
$self instvar node_
#encap settings
set clsfr_dst [$node_ set dst_classifier_]
set encap [$node_ get-pmip6-encap $te]
$clsfr_dst install-by-dest $mnaddr $encap }

53. LMA Operation (6/7) get-pmip6-encap 함수 (TCL)
Tunneling endpoint(te)에 대한 PMIPv6Encapsulator 얻기
TE가 존재하면 재사용, 없으면 새로 생성
Node instproc get-pmip6-encap { te } {
$self instvar address_ Encaps_
if {[info exists Encaps_($te)] && $Encaps_($te) != ""} {
return $Encaps_($te) }
set Encaps_($te) [new PMIPv6Encapsulator]
$Encaps_($te) set addr_ [AddrParams addr2id $address_]
$Encaps_($te) set port_ [Simulator set PMIPv6_TUNNEL_PORT]
$Encaps_($te) set dest_addr_ $te
$Encaps_($te) set dest_port_ [Simulator set PMIPv6_TUNNEL_PORT]
$Encaps_($te) target [$self entry]
$Encaps_($te) set node_ $self
return $Encaps_($te) }

54. LMA Operation (7/7)

55. MAG Operation #2 (1/5) Receiving PBACK PMIPv6Agent MAGAgent recv()
process_packet()
process_pback()
-find_bule()
setup_route()
bule_state: BUL_S_SETUP
setup-route/TCL
-get-pmip6-encap/TCL
clear_route()
bule_state: BUL_S_DELETE
clear-route/TCL

56. MAG Operation #2 (2/5) process_pback 함수 bule 갱신, routing 설정
void MAGAgent::process_pback(Packet* p) {
hdr_pmipv6 *h = hdr_pmipv6::access(p);
BULEntry *bule;
bule = find_bule(h->mn_id()); ……
//Stop retransmit timer
bule->BULTimer_.cancel();
bule->mn_prefix() = h->haddr();
bule->lifetime() = h->lifetime();
switch(bule->get_state()) {
case BUL_S_SETUP:
setup_route(bule);
//fall through
case BUL_S_REFRESH:
//Update lifetime for binding refresh
bule->BULTimer_.resched(
(double)bule->lifetime()*.9);
if(bule->pktPBU_) {
Packet::free(bule->pktPBU_);
bule->pktPBU_ = 0; }
bule->set_state(BUL_S_ESTABLISHED);
break;
case BUL_S_DELETE:
clear_route(bule);
bule->remove_entry();
delete bule;

57. MAG Operation #2 (3/5) setup-route 함수 (TCL)
PMIPv6Decapsulator에 MN의 link 등록
MN이 무선노드이면 adhoc routing protocol을 target으로 지정
MN이 일반 노드이면 link 검색 후 target 지정
MN의 주소의 패킷이 PMIPv6Encapsulator로 전달되도 록 PMIPv6Src classifier에 등록

58. MAG Operation #2 (4/5) setup-route 함수 (TCL) (cont’d)
Agent/PMIPv6/MAG instproc setup-route { mnaddr te} {
$self instvar node_
set ns [Simulator instance]
set decap_ [$node_ set decap_]
if {[$node_ info class] == "MobileNode/MIPBS" ||
[$node_ info class] =="Node/MobileNode" } {
set target [$node_ set ragent_]
} else {
set target [[$ns link $node_ [$ns get-node-by-addr $mnaddr]] head]
if {$target==""} { puts "cannot find target“ } }
$decap_ install $mnaddr $target
set clsfr_src [$node_ set src_classifier_]
set encap [$node_ get-pmip6-encap $te]
$clsfr_src install-by-src $mnaddr $encap

59. MAG Operation #2 (5/5)

60. Encap/Decap Operation (1/3)
PMIPv6Src
Classifier가 IP헤더의 source address로 hash하 도록 classify 함수 변경
PMIPv6Dest
기존 address classifier 그대로 사용
int PMIPv6Src::classify(Packet *p) {
hdr_ip* iph = hdr_ip::access(p);
return mshift(iph->saddr()); }

61. Encap/Decap Operation (2/3)
PMIPv6Encapsulator의 recv 함수
MAG와 LMA의 setup-route(TCL)함수에 의하여 MN의 data packet은 PMIPv6Encapsulator의 recv 를 호출하도록 설정되어있음
void PMIPv6Encapsulator::recv(Packet* p, Handler *h) {
hdr_cmn* ch = hdr_cmn::access(p);
hdr_ip* hdr = hdr_ip::access(p);
hdr_ip6encap *enh = HDR_IP6ENCAP(p);
if (--hdr->ttl_ <= 0) {
Packet::free(p); return; }
enh->hdr_ = *hdr;
enh->ptype_ = ch->ptype();
hdr->saddr() = here_.addr_;
hdr->sport() = here_.port_;
hdr->daddr() = dest_.addr_;
hdr->dport() = dest_.port_;
hdr->ttl() = defttl_;
ch->size() += IPv6_HEADER_SIZE;
target_->recv(p,h); }

62. Encap/Decap Operation (3/3)
PMIPv6Decapsulator의 recv 함수
외부 헤더와 내부 헤더를 교환
void PMIPv6Decapsulator::recv(Packet* p,
Handler *h) {
hdr_cmn* ch = hdr_cmn::access(p);
hdr_ip *hdr = hdr_ip::access(p);
hdr_ip6encap *enh = HDR_IP6ENCAP(p);
hdr_ip tmph;
tmph = *hdr;
*hdr = enh->hdr_;
enh->hdr_ = tmph;
NsObject* link = find(p);
if (link == NULL || hdr->ttl_ <= 0) {
printf("Link not found\n");
Packet::free(p);
return; }
ch->size() -= IPv6_HEADER_SIZE;
link->recv(p,h);