ATM(asynchronous transfer mode,\u975e\u540c\u6b65\u50b3\u8f38\u7db2\u8def)
\u9023\u7d50\u5c0e\u5411\u5f0f,1990
\u5927\u90e8\u4efd\u88ab\u96fb\u4fe1\u696d\u8005\u7528\u65bc\u5167\u90e8\u50b3\u8f38,LAN\u6280\u8853\u548cWAN\u6280\u8853\u5dee\u4e0d\u591a
\u4f7f\u7528\u975e\u540c\u6b65\u5206\u6642\u591a\u5de5
\u652f\u63f4\u865b\u64ec\u7dda\u8defPVC,SVC(\u9700\u8981\u7db2\u8def\u5c64\u4f4d\u5740\u53ca\u5176\u4ed6\u5354\u5b9a\u5e6b\u5fd9)
\u9001\u5c01\u5305\u6642\u6cbf\u8def\u7531\u5668\u8a18\u9304\u7684\u9023\u7d50\u8cc7\u6599,\u985e\u4f3c\u96fb\u8a71\u7684\u5c08\u7dda
\u4ee553byte\u56fa\u5b9a\u5927\u5c0f,\u5c0f\u5305cell:header(5byte)+\u8cc7\u6599(48byte)\u50b3\u9001
\u56fa\u5b9a\u5927\u5c0f\u8f03\u5feb,\u8b8a\u52d5\u9577\u5ea6ip\u5c01\u5305\u9808\u7531\u8edf\u9ad4\u8def\u7531,\u7a0b\u5e8f\u8f03\u6162
header\u5167\u7684\u9023\u7d50\u8b58\u5225\u78bc,\u53ef\u8fa6\u5225\u5c0f\u5305\u5c6c\u65bc\u90a3\u500b\u9023\u7d50
\u53ef\u900f\u904e\u786c\u9ad4\u5c07\u5c0f\u5305\u8907\u88fd\u5230\u591a\u8f38\u51fa\u7dda\u8def
\u5c0f\u5305\u7686\u4f9d\u5faa\u9001\u9054
\u4fdd\u8b49\u670d\u52d9\u54c1\u8cea\u5bb9\u6613\u505a\u5230:\u56e0\u5c0f\u5305\u4e0d\u9577\u6642\u9593\u4f54\u7528\u7dda\u8def
\u9069\u7528\u65bc1.544Mbps(T1),40.736Mbps(T3)\u4ee5\u4e0a\u53ca\u50b3\u9001\u6578\u64da\u3001\u8a9e\u97f3\u3001\u8996\u8a0a\u7b49\u591a\u5a92\u9ad4\u6574\u5408\u7684\u7db2\u8def
\u50b3\u8f38\u901f\u7387\u5305\u542b 622Mbps(OC-12)\u3001155Mbps(OC-3)\u3001100Mbps\u300151Mbps\u300125Mbps \u7b49\u7b49\u3002\u4ee5155Mbps \u6700\u70ba\u5e38\u7528
\u5177\u5fae\u8abf\u529f\u80fd\u7684\u670d\u52d9\u54c1\u8cea,\u6709\u8a31\u591a\u63cf\u8ff0qos\u65b9\u6cd5(cbr,vbr,abr)
B-ISDN\u662f\u63d0\u4f9b\u670d\u52d9\u7684\u7cfb\u7d71,\u9700\u8981ATM\u7684\u7d30\u80de\u50b3\u8f38\u3001\u4ea4\u63db\u3001\u548c\u591a\u5de5\u7684\u6280\u8853
SONET\u662f\u50b3\u8f38ATM\u7d30\u80de\u7684\u5be6\u9ad4\u5e79\u7dda,\u5176\u50b3\u8f38\u901f\u7387\u53ef\u75311.5Mbps\u523010 Gbps
\u53ef\u4ee5\u4f5c\u70baframe relay,x.25,\u5176\u4ed6\u7db2\u8def\u7684\u9aa8\u5e79\u7db2\u8def
\u76ee\u524d\u4e16\u754c\u5404\u570b\u6240\u81f4\u529b\u65bc\u767c\u5c55\u7684NII(National Information Infrastructure,\u570b\u5bb6\u8cc7\u8a0a\u57fa\u790e\u5efa\u8a2d)\u7684\u57fa\u672c\u67b6\u69cb<\/p>\n\n\n\n
\u722d\u8b70
\u9001\u4e00\u500b\u5c01\u5305\u6703\u5efa\u7acbVC\u9023\u7dda,\u6642\u9593\u904e\u9577
\u8868\u982d\u4f54\u7d30\u530510%(\u7d30\u5305\u7a05)
\u5efa\u9023\u7dda\u6642\u4e0d\u77e5\u9078\u4f55\u7a2e\u9069\u7576\u7684\u670d\u52d9\u53c3\u6578
NBMA\u4e0d\u63d0\u4f9b\u5ee3\u64ad\u6216\u7fa4\u64ad\u7684\u529f\u80fd,\u9023\u7dda\u5c0e\u5411\u9700\u7528\u6a21\u64ec\u65b9\u5f0f\u5be6\u73fe\u5ee3\u64ad\u529f\u80fd
\u983b\u5bec\u4e0d\u5920\u6642\u5fae\u8abf\u529f\u80fd\u4e0d\u9700\u8981,\u983b\u5bec\u8db3\u5920\u4e0d\u9700\u5fae\u8abf
\u548c\u5176\u4ed6\u7db2\u8def\u6280\u8853\u9593\u6c92\u6709\u4ec0\u9ebc\u5354\u529b\u904b\u4f5c\u7a7a\u9593<\/p>\n\n\n\n
…………………………………………<\/p>\n\n\n\n
PVC\u7531\u7db2\u8def\u63d0\u4f9b\u8005\u5efa\u56fa\u5b9a\u9023\u7dda
SVC\u52d5\u614b\u9023\u7dda\u5efa\u7acb\u8207\u91cb\u653e
1.\u5de5\u4f5c\u7ad9A\u50b3\u9001\u4e00\u5247SETUP\u8a0a\u606f\u5c0d\u76f4\u63a5\u76f8\u9023\u7684ATM\u4ea4\u63db\u6a5f1
SETUP\u8a0a\u606f\u542b\uff1a\u5de5\u4f5c\u7ad9B\u768420byte ATM \u4f4d\u5740\u53ca\u9023\u7dda\u6240\u9700QoS\u53c3\u6578\u3002
2.ATM\u4ea4\u63db\u6a5f1\u5206\u6790SETUP\u8a0a\u606f,\u56de\u61c9\u65b9\u5f0f\u6709\u5169\u7a2e\uff1a
\u627e\u5230\u5de5\u4f5c\u7ad9B\u7684\u4ea4\u63db\u6a5f\u4f4d\u5740\u53ca\u53ef\u652f\u63f4\u9023\u7dda\u6240\u9700\u7684QoS\u53c3\u6578\uff0c\u5247\u5c07CALL PROCEEDING\u8a0a\u606f\u9001\u56de\u5230\u5de5\u4f5c\u7ad9 A
\u672a\u627e\u5230\u5de5\u4f5c\u7ad9B\u7684\u4ea4\u63db\u6a5f\u4f4d\u5740\u6216\u7121\u6cd5\u63a5\u53d7\u6b64\u9023\u7dda\uff0c\u5247\u5411\u5de5\u4f5c\u7ad9A\u9001\u56de\u5305\u542b\u6a19\u6e96\u932f\u8aa4\u4ee3\u78bc\u7684 RELEASE \u8a0a\u606f\uff0c\u4e26\u62d2\u7d55\u6b64\u547c\u53eb\u8981\u6c42
3.ATM\u4ea4\u63db\u6a5f1\u6703\u767c\u9001SETUP\u8a0a\u606f\u81f3ATM\u4ea4\u63db\u6a5f2
ATM\u4ea4\u63db\u6a5f2\u6703\u63a5\u6536SETUP\u8a0a\u606f,\u5047\u8a2d\u7cfb\u7d71\u5224\u5b9a\u5de5\u4f5c\u7ad9B\u5728ATM\u4ea4\u63db\u6a5f2\u4e0a\u767b\u9304\u7684\u76f4\u63a5\u9023\u7dda\u7aef\u9ede\u4e14\u53ef\u4ee5\u63a5\u53d7\u8981\u6c42\u9023\u7dda\u6240\u9700\u7684QoS
ATM\u4ea4\u63db\u6a5f2\u6703\u5c07CALL PROCEEDING \u8a0a\u606f\u9001\u56de\u5230ATM\u4ea4\u63db\u6a5f1
4.SETUP\u8a0a\u606f\u5230\u9054\u5de5\u4f5c\u7ad9B\u3002\u56de\u61c9\u65b9\u5f0f\u6709\u5169\u7a2e\uff1a
\u5de5\u4f5c\u7ad9B\u63a5\u53d7\u6b64\u547c\u53eb\uff0c\u6703\u5411ATM\u4ea4\u63db\u6a5f2\u50b3\u9001CALL PROCEEDING\u8a0a\u606f\uff0c\u5176\u5f8c\u7dca\u63a5CONNECT\u8a0a\u606f
\u5de5\u4f5c\u7ad9B\u62d2\u7d55\u6b64\u547c\u53eb\uff0c\u5c31\u5c07RELEASE \u8a0a\u606f\u9001\u56deATM\u4ea4\u63db\u6a5f2\u3002\u6b64RELEASE\u8a0a\u606f\u900f\u904e\u7db2\u8def\u50b3\u56de\u5230\u5de5\u4f5c\u7ad9A\uff0c\u5305\u542b\u63cf\u8ff0\u62d2\u7d55\u539f\u56e0\u7684\u6a19\u6e96\u932f\u8aa4\u4ee3\u78bc
5.ATM\u4ea4\u63db\u6a5f2\u6703\u5c07 CONNECT ACK\u8a0a\u606f\u9001\u56de\u5230\u7aef\u9ede\u5de5\u4f5c\u7ad9 B\uff0c\u7136\u5f8c\u50b3\u905e CONNECT \u8a0a\u606f\u5230 ATM \u4ea4\u63db\u6a5f 1
ATM\u4ea4\u63db\u6a5f1\u5c07 CONNECT ACK\u8a0a\u606f\u9001\u56de\u5230ATM\u4ea4\u63db\u6a5f2\uff0c\u7136\u5f8c\u50b3\u905e CONNECT\u8a0a\u606f\u5230\u5de5\u4f5c\u7ad9 A
\u5de5\u4f5c\u7ad9 A \u5411 ATM \u4ea4\u63db\u6a5f 1 \u9001\u56de CONNECT ACK \u8a0a\u606f\u3002<\/p>\n\n\n\n
vpi\/vci
TP(transmission path,\u50b3\u8f38\u901a\u9053)\uff1a\u5169\u7aef\u9ede\u9593\u5be6\u9ad4\u63a5\u7dda,\u4e14\u88ab\u5207\u5272\u6210\u591aVP
vpi(virtual path identifier,\u865b\u64ec\u8def\u5f91\u4ee3\u78bc) 8bit:\u7528\u4f86\u63cf\u8ff0\u4e00\u689dvp(virtual path,\u865b\u64ec\u901a\u9053)
vci(virtual channel identifier,\u865b\u64ec\u901a\u9053\u4ee3\u78bc) 16bit:\u7528\u4f86\u63cf\u8ff0vp\u5167\u7684\u4e00\u689dvc(virtual circuits,\u865b\u64ec\u96fb\u8def)
label rewriting(\u6a19\u5343\u8986\u5beb):atm\u4ea4\u63db\u6a5f\u6703\u66f4\u63db\u6bcf\u500b\u7d30\u5305\u7684vpi\/vci\u6b04\u4f4d
atm\u4ea4\u63db\u6a5f,\u4e5f\u7a31\u70balabel switching system(\u6a19\u5343\u4ea4\u63db\u7cfb\u7d71)
\u4e00\u500batm\u7db2\u8def\u7531\u591a\u90e8atm\u4ea4\u63db\u6a5f\u8a2d\u5099\u7d44\u5408\u800c\u6210
UNI(user-to-network interface,\u4f7f\u7528\u8005\u7db2\u8def\u754c\u9762)\uff1a\u8b93\u7aef\u9ede\u9023\u5230atm\u7db2\u8def
NII(network-to-network interfaces,\u7db2\u8def\u9593\u754c\u9762)\uff1a\u4ea4\u63db\u6a5f\u5f7c\u6b64\u76f8\u9023\u4ecb\u9762
\u4ea4\u63db\u6a5f\u5167\u5132\u5b58forwarding table(\u8f49\u9001\u8868)\uff1a\u7528\u4f86\u8a2d\u5b9a\u786c\u9ad4\u5982\u4f55\u8f49\u9001\u7d30\u5305\u7684\u8cc7\u8a0a
\u5178\u578b\u4ea4\u63db\u6a5f\u57e0\u5728oc-3(155mbps)\u4ee5\u4e0a\u9ad8\u901f\u904b\u4f5c
\u6602\u8cb4 <\/p>\n\n\n\n
………………………………………….<\/p>\n\n\n\n
ATM\u53c3\u8003\u6a21\u5f0f
user plane(\u4f7f\u7528\u8005\u5e73\u9762)\uff1a
\u8ca0\u8cac\u7528\u6236\u8a0a\u606f\u4e4b\u8655\u7406\u53ca\u50b3\u9001\uff0c\u53e6\u5916\u4ea6\u5305\u542bF1ow Contro1(\u6d41\u91cf\u63a7\u5236)\u53caError Recovery(\u932f\u8aa4\u5fa9\u539f)\u529f\u80fd\u3002
\u5206\u6210\u56db\u5c64:\u9ad8\u5c64\u3001AAL\u3001ATM Layer\u3001\u5be6\u9ad4\u5c64\u3002
\u9ad8\u5c64\u56e0\u670d\u52d9\u7b49\u7d1a\u4e0d\u540c\u53ef\u5206\u6210\uff1aCBR,VBR,ABR,UBR
control plane(\u63a7\u5236\u5e73\u9762)\uff1a\u9023\u7d50\u7ba1\u7406
\u57f7\u884c\u512a\u5148\u65bc\u7528\u6236\u9762\uff0c\u4e14\u70baLink by Link(\u93c8\u8def\u5c0d\u93c8\u8def)\u4e4b\u5efa\u7acb\u65b9\u5f0f
\u8ca0\u8cac\u547c\u53eb\u63a7\u5236\u548c\u63a5\u7e8c\u63a7\u5236\u529f\u80fd\uff0c\u7528\u4f86\u5efa\u7acb\u7528\u6236\u9762\u6240\u9700\u4e4b\u8def\u7531\u8cc7\u8a0a\u53ca\u5176\u63a5\u7e8c\u6240\u9700\u4e4b\u670d\u52d9\u7b49\u7d1a\u3002
\u8207Call Set UP(\u547c\u53eb\u5efa\u7acb)\u3001Supervisory(\u76e3\u7763)\u8207Release(\u91cb\u653e)\u7b49\u547c\u53eb\u7a0b\u5e8f\u6709\u95dc\u4e4b\u529f\u80fd\u7686\u7531\u63a7\u5236\u9762\u57f7\u884c\u3002
\u5206\u6210\u56db\u5c64\uff1a\u4e09\u5c64user plane\u76f8\u540c\uff0c\u4e0d\u540c\u8005\u5728\u9ad8\u5c64\uff0c
ATM SVC(Switched Virtual Circuit)\u4fe1\u865f\u65b9\u5f0f\u5373\u9808\u7531\u63a7\u5236\u9762\u57f7\u884c\uff0c\u4f8b\u5982Q.293l\u4fe1\u865f\u3001PNNI\u4fe1\u865f\u3001A-INI\u4fe1\u865f\u5354\u5b9a\u7b49\u3002
\u7ba1\u7406\u9762\uff1a\u5c64\u6b21\u9593\u5354\u8abf,\u542bPlane Management(\u9762\u7ba1\u7406)\u8207Layer management(\u5c64\u7ba1\u7406)\u529f\u80fd
\u9762\u7ba1\u7406\uff1a\u7121\u5c64\u6b21\u5316\u67b6\u69cb,\u8655\u7406\u4e09\u500b\u9762\u4e4b\u9593\u7684\u5354\u8abf,\u51e1\u8207\u7cfb\u7d71\u6574\u9ad4\u6709\u95dc\u7684\u7ba1\u7406\u529f\u80fd\u5747\u7531\u9762\u7ba1\u7406\u8ca0\u8cac\u3002
\u5c64\u7ba1\u7406\uff1a\u5177\u6709\u968e\u5c64\u67b6\u69cb,\u8ca0\u8cac\u57f7\u884cProtocol Entities(\u5354\u5b9a\u5be6\u9ad4)\u5167\u6709\u95dc\u8cc7\u6e90\u8207\u53c3\u6578\u4e4b\u7ba1\u7406
ex:Meta-signaling(\u524d\u7f6e\u4fe1\u865f)\u529f\u80fd\uff0c\u53e6\u5916\u5404\u898f\u7d04\u5c64\u4e4bOAM(Operation and Maintenance,\u64cd\u4f5c\u548c\u7dad\u8b77)\u529f\u80fd\u4ea6\u7531\u5c64\u7ba1\u7406\u57f7\u884c\u3002<\/p>\n\n\n\n
\u985e\u4f3c\u8cc7\u8a0a\u93c8\u7d50\u5c64\u7684LLC
AAL(application adaptation layer,\u61c9\u7528\u8abf\u9069\u5c64)\uff1a\u5bb9\u8a31\u65e2\u6709\u7db2\u8def\u9023\u63a5\u5230atm\u8a2d\u65bd\u4e2d
\u63a5\u53d7\u5f9e\u4e0a\u5c64\u670d\u52d9\u50b3\u4f86\u7684\u8cc7\u6599,\u4e26\u5c07\u4e4b\u5c0d\u61c9\u5230\u56fa\u5b9a\u5927\u5c0f\u7684atm\u7d30\u80de,aal\u5206\u5169\u5c64
CS(convergence sublayer,\u6536\u6582\u5b50\u5c64):
SAR(segmentation and reassembly,\u5206\u5272\u8207\u91cd\u7d44\u5b50\u5c64):\u5207\u5272\u5927\u5c01\u5305\u6210\u5c0f\u5305,\u91cd\u7d44\u5c0f\u5305
\u6709aal1-aal5:
AAL1:\u652f\u63f4CBR,\u5982\u8996\u8a0a\u8a9e\u97f3,\u5bb9\u8a31ATM\u9023\u63a5\u5230\u6578\u4f4d\u96fb\u8a71\u7db2\u8def,\u5982DS-3\u6216E1
SAR\u52a0\u4e86header1byte:csi(cs\u8b58\u5225\u78bc1bit)+sc(\u5e8f\u5217\u8a08\u65783bit)+crc(3bit)+p(\u540c\u4f4d\u6aa2\u67e51bit)
AAL2:\u652f\u63f4VBR,\u91dd\u5c0d\u7c21\u55ae\u7684\u3001\u9762\u5411\u9023\u63a5\u7684\u3001\u5be6\u6642\u6578\u64da\u6d41\u800c\u8a2d\u8a08\u7684
SAR\u52a0header:csi(1bit)+sc(3bit)+it(\u8b58\u5225\u8cc7\u6599\u5340\u6bb5\u5728\u90a34bit),\u53ca\u8868\u5c3e:LI(\u9577\u5ea6\u6307\u793a\u5b506bit)+crc(10bit)
AAL3\/4:\u652f\u63f4ABR,3\u652f\u63f4\u9023\u7dda\u5c0e\u5411\u8cc7\u6599\u670d\u52d9,4\u652f\u63f4\u975e\u9023\u7dda\u5f0f\u670d\u52d9,\u6709\u53ef\u9760\u53ca\u4e0d\u53ef\u9760\u50b3\u8f38
\u63a5\u6536\u4e0a\u5c64\u670d\u52d9(SMDS,frame relay)\u7684\u8cc7\u6599\u5c01\u5305,\u63d0\u4f9b\u5b8c\u6574\u6392\u5e8f\u53ca\u932f\u8aa4\u63a7\u5236,\u8f03\u8907\u96dc\u4f46\u53ef\u9760\u6027\u8f03\u9ad8
CS\u52a0\u4e86header:T(type1bit)+BT(\u958b\u59cbtable1bit)+BA(\u7de9\u885d\u914d\u7f6e2bit),\u53ca\u8868\u5c3e:pad+al(\u6821\u6e961bit)+et(\u7d50\u675ftabel1bit)+l(\u9577\u5ea62bit)
SAR\u52a0\u4e86header:st(2bit)+csi(1bit)+sc(3bit)+mid(\u591a\u5de5\u8b58\u522510bit),\u53ca\u8868\u5c3e:LI(6bit)+crc(10bit)
AAL5:\u652f\u63f4ABR,\u4e5f\u7a31SEAL\u7c21\u6613\u6709\u6548\u8abf\u9069\u5c64,\u652f\u63f4\u9ede\u5c0d\u9ede\u53ca\u591a\u9ede\u50b3\u64ad,\u8f03AAL3\/4\u66f4\u52a0\u9ad8\u6548,\u4e0d\u63d0\u4f9b\u5b9a\u5740,\u6392\u5e8f,\u6216\u5176\u4ed6CS,SAR\u4e2d\u8868\u982d\u8cc7\u8a0a
\u63d0\u4f9b\u53ef\u9760\u670d\u52d9\u8207\u4e0d\u53ef\u9760\u670d\u52d9,\u652f\u63f4\u9023\u7dda\u5c0e\u5411\u8207\u975e\u9023\u7dda\u5f0f\u670d\u52d9,\u53ef\u50b3ip\u5c01\u5305,\u76ee\u524d\u70ba\u5546\u54c1\u5316\u7cfb\u7d71\u4e2d\u6700\u666e\u904d\u8005
CS\u542b\u8868\u5c3e:pad+UU(\u4f7f\u7528\u8005\u5c0d\u4f7f\u7528\u8005ID1bit)+T(type1bit)+L(\u9577\u5ea62bit)+crc(4bit) <\/p>\n\n\n\n
\u985e\u4f3c\u8cc7\u6599\u93c8\u7d50\u5c64\u7684MAC
ATM layer:\u63d0\u4f9b\u8def\u7531,\u8a0a\u52d9,\u6d41\u91cf\u63a7\u5236,\u4ea4\u63db\u548c\u591a\u5de5,\u8ca0\u8cac\u8655\u7406\u5c0f\u5305\u9593\u50b3\u8f38,\u5224\u65b7\u8868\u982d\u6b04\u610f\u7fa9,VC\u8def\u5f91\u7ba1\u7406,\u8655\u7406\u5efa\u7acb\u91cb\u653e\u96cd\u585e\u63a7\u5236
\u5c07\u4f86\u81eaaal\u5c64\u768448bytes\u5340\u6bb5\u52a0\u4e0a5byte\u7684header
header 5byte,\u6709\u7d66UNI\u754c\u9762\u548cNNI\u754c\u9762\u5169\u7a2e\u683c\u5f0f
GFC(\u901a\u7528\u6d41\u91cf\u63a7\u5236)4bit,\u53ea\u6709UNI\u6709
vpi UNI\u662f8bit,NNI\u662f10bit
vci 16bit
PTI 3bit \u8a18\u9304\u8cc7\u6599\u578b\u5225
CLP 1bit \u512a\u5148\u6b04\u4f4d,1\u8868\u8981\u4fdd\u7559,\u9810\u8a2d\u70ba0
HEC(\u8868\u982d\u932f\u8aa4\u63a7\u5236)8bit\uff1a\u7528crc(cyclic redundancy check,\u5faa\u74b0\u5197\u9918\u6aa2\u67e5\u6b04\u4f4d)
\u5be6\u9ad4\u5c64
TC(\u50b3\u8f38\u805a\u5408\u5b50\u5c64):\u5c07\u4f4d\u5143\u6d41\u548c\u5c0f\u5305\u8f49\u63db\u7d66\u4e0a\u4e0b\u5c64
PMD(\u5be6\u9ad4\u5a92\u4ecb\u5f9e\u5c6c\u5b50\u5c64):\u8ca0\u8cac\u79fb\u52d5\u4f4d\u5143,\u4e0d\u540c\u7dda\u8def\u6b64\u5c64\u6703\u4e0d\u540c
ATM Forum\u5236\u8a02\u7684\u9ad8\u901f\u50b3\u8f38\u5a92\u4ecb\uff1a
155.520Mbps\u65bcsingle-mode(\u55ae\u6a21)\u6216multi-mode(\u591a\u6a21)\u4e4b\u5149\u7e96\u3002
155.520Mbps\u65bc\u591a\u6a21\u5149\u7e96\u6216shielded twisted pair(\u906e\u853d\u5f0f\u96d9\u7d5e\u7dda)\uff0c\u4e26\u4f7f\u75288B\/10B\u4e4b\u7de8\u78bc\u3002
100Mbps\u65bc\u591a\u6a21\u5149\u7e96\uff0c\u4e26\u4f7f\u75284B\/5B\u4e4b\u7de8\u78bc\u3002
44.736Mbps\u65bccoaxial cable(\u540c\u8ef8\u96fb\u7e9c)\u3002
ATM Forum\u5236\u8a02\u7684\u4f4e\u901f\u50b3\u8f38\u5a92\u4ecb\uff1a
51.840Mbps category-3 \u975e\u906e\u853d\u5f0f\u96d9\u7d5e\u7dda
155.520Mbps category-5 \u975e\u906e\u853d\u5f0f\u96d9\u7d5e\u7dda
\u6b50\u6d32\u6a19\u6e96\u901f\u7387 34.368Mbps(E3)\u548c139.264Mbps(E4)
\u66f4\u4f4e\u901f\u76841.544Mbps(DS-1 or T-1)\u548c2.048Mbps(E1)\u3002<\/p>\n\n\n\n
AAL\u5c64\u65e9\u671f\u56db\u985e\u670d\u52d9
class a:\u9023\u7d50\u5c0e\u5411,\u5373\u6642\u50b3\u9001,\u56fa\u5b9a\u901f\u7387
class b:\u9023\u7d50\u5c0e\u5411,\u5373\u6642\u50b3\u9001
class c:\u9023\u7d50\u5c0e\u5411
class d:<\/p>\n\n\n\n
…………………………………….<\/p>\n\n\n\n
atm\u7db2\u8def\u6839\u64daqos\u8981\u6c42\u5c07\u8cc7\u6599\u6d41\u5206\u70ba\u56db\u7a2e Traffic Contract(\u8a0a\u52d9\u5408\u7d04):\u5c6c\u65bcATM Traffic Management(\u8a0a\u52d9\u7ba1\u7406)\u529f\u80fd ATM\u4f7f\u7528\u8005\u8207UNI\u7684\u8a0a\u865f\u6a19\u6e96\u6709\u4e09\uff1a SAAL(Signaling AAL,\u8a0a\u865fATM\u8abf\u7bc0\u5c64):\u50b3\u8f38\u670d\u52d9\u57fa\u672c\u4e0a\u662f\u5c6c\u65bcAAL5\u7684\u578b\u614b ATM \u7db2\u8def\u8207\u50b3\u7d71\u7db2\u8def\u4e92\u9023\u7684\u4e8c\u7a2e\u65b9\u6cd5 ………………………………<\/p>\n\n\n\n LAN emulation(\u5340\u57df\u7db2\u8def\u4eff\u6548) \u53ef\u89e3\u6c7a\u7684\u554f\u984c LAN Emulation Over ATM,\u5728ATM\u4e0a\u9032\u884c\u5340\u57df\u7db2\u8def\u6a21\u64ec\u7684\u6280\u8853 LANE\u6280\u8853\u4e3b\u8981\u7528\u5230\u4e86 ATM(asynchronous transfer mode …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[28],"tags":[],"class_list":["post-837","post","type-post","status-publish","format-standard","hentry","category-wan"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/837","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/comments?post=837"}],"version-history":[{"count":0,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/837\/revisions"}],"wp:attachment":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/media?parent=837"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/categories?post=837"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/tags?post=837"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\u512a\u51481,CBR(constant bit rate,\u56fa\u5b9a\u4f4d\u5143\u901f\u7387) \u53c8\u7a31Circuit Emulation(\u7dda\u8def\u6a21\u64ec\u670d\u52d9) ex:\u96fb\u8a71
\u56fa\u5b9a\u901f\u7387\u7684\u670d\u52d9\uff0c\u5c0d\u50b3\u8f38\u5ef6\u9072\u3001\u50b3\u8f38\u907a\u5931\u53ca\u50b3\u8f38\u8df3\u52d5\u7b49\u670d\u52d9\u54c1\u8cea\u8981\u6c42\u6700\u56b4\u683c Class A
\u63d0\u4f9b\u7528\u6236\u56fa\u5b9a\u7684\u983b\u5bec\uff0c\u53ef\u61c9\u7528\u5728\u9ad8\u89e3\u6790\u5ea6\u7684\u8996\u8a0a\u3001\u8a9e\u97f3\u3001\u96fb\u8def\u6a21\u64ec\u7b49\u5373\u6642\u6027\u670d\u52d9
\u512a\u51482,VBR(variable bit rate,\u8b8a\u52d5\u4f4d\u5143\u901f\u7387)
\u63d0\u4f9b\u4e86\u5c0d\u50b3\u8f38\u5ef6\u9072\u548c\u50b3\u8f38\u907a\u5931\u7684\u4fdd\u8b49 Class B
rt-VBR(real-time,\u5373\u6642\u8b8a\u52d5\u4f4d\u5143\u901f\u7387) ex:\u58d3\u7e2e\u5f0f\u8996\u8a0a\u6703\u8b70
\u53ef\u61c9\u7528\u65bc\u7a81\u767c\u6027\u4e14\u5373\u6642\u6027\u7684\u8cc7\u6599\u670d\u52d9\uff0c\u5982\uff1a\u5373\u6642\u7403\u8cfd\u3001\u6f14\u5531\u6703\u8f49\u64ad\u53ca\u8996\u8a0a\u6703\u8b70\u7b49
nrt-VBR(non-real-time,\u975e\u5373\u6642\u8b8a\u52d5\u4f4d\u5143\u901f\u7387) ex:\u96a8\u9078\u8996\u8a0a
\u61c9\u7528\u65bc\u822a\u7a7a\u8a02\u4f4d\u3001\u9280\u884c\u4ea4\u6613\u7b49\u5177\u7a81\u767c\u6027\u4f46\u7121\u9808\u5373\u6642\u53cd\u61c9\u4e4b\u8cc7\u6599\u670d\u52d9
\u512a\u51483,ABR(available bit rate,\u53ef\u7528\u4f4d\u5143\u901f\u7387) ex:\u6a94\u6848\u50b3\u8f38
Class C,D
\u6700\u4f4e\u901f\u7387\u50b3\u8f38,\u5982\u6709\u591a\u9918\u983b\u5bec\u5373\u53ef\u4f7f\u7528,\u9069\u5408IP\u548cLAN\u670d\u52d9,\u53ca\u7a81\u7206\u6027\u8cc7\u6599\u50b3\u8f38,\u4e0d\u505a\u58c5\u585e\u63a7\u5236
\u61c9\u7528\u65bc\u5ee3\u57df\u8207\u5340\u57df\u7db2\u8def\u4e92\u9023\u3001\u5206\u6563\u5f0f\u8cc7\u6599\u50b3\u9001\uff0c\u5982\u4e00\u822cISP\u7db2\u969b\u7db2\u8def\u670d\u52d9\u516c\u53f8
UBR(Unspecified Bit Rate,\u672a\u78ba\u5b9a\u901f\u7387)\uff1a\u4f7f\u7528\u5269\u9918\u983b\u5bec,\u9069\u5408\u7684\u670d\u52d9\u8207ABR\u76f8\u540c\uff0c\u4f46\u7121\u4efb\u4f55\u670d\u52d9\u4fdd\u8b49,\u4e0d\u505a\u58c5\u585e\u63a7\u5236
GFR(Guaranteed Frame Rate) UBR<\/strong>+<\/p>\n\n\n\n
\u5c0dPVC\u800c\u8a00\uff0c\u8a0a\u52d9\u5408\u7d04\u4fc2\u65bc\u7528\u6236\u7533\u8acb\u6642\u5373\u7531\u7db2\u8def\u7ba1\u7406\u55ae\u4f4d\u4ee3\u70ba\u8a2d\u5b9a\u3002
\u5c0dSVC\u800c\u8a00\uff0c\u8a0a\u52d9\u5408\u7d04\u4fc2\u7531\u7528\u6236\u65bc\u547c\u53eb\u5efa\u7acb\u6642\u4ee5\u63a7\u5236\u9762\u7684\u4fe1\u865f\u5354\u5b9a\u8207\u4ea4\u63db\u6a5f\u5354\u5546\u800c\u8a02\u51fa\u8a0a\u52d9\u5408\u7d04\u3002
\u8a0a\u52d9\u53c3\u6578\u4e3b\u8981\u4ee5PCR(Peak Cell Rate,\u5cf0\u503c\u7d30\u5305\u901f\u7387),SCR(Sustainable Cell Rate,\u6301\u7e8c\u7d30\u5305\u901f\u7387),\u8868\u793a\u5e73\u5747\u7d30\u5305\u901f\u7387,MBS(Maximum Burst Size,\u6700\u5927\u53e2\u805a\u91cf),MCR(Minimum Cell Rate,\u6700\u5c0f\u7d30\u5305\u901f\u7387)\u70ba\u8a55\u91cf\u6a19\u6e96\u9805\u76ee\u3002
\u670d\u52d9\u54c1\u8cea\u53c3\u6578\u4e3b\u8981\u4ee5Cell Delay(\u7d30\u5305\u5ef6\u9072)\u548cCLR(Cell Loss Ratio,\u7d30\u5305\u6f0f\u5931\u6bd4\u503c)\u70ba\u8a55\u91cf\u6a19\u6e96\u9805\u76ee
\u6aa2\u9a57\u7d30\u5305\u662f\u5426\u9075\u5f9e\u6216\u8005\u662f\u975e\u9075\u5f9e\u5176\u8a0a\u52d9\u5408\u7d04\u4e4b\u898f\u5b9a\u4f7f\u7528GCRA(Generic Cell Rate Algorithm)
\u4f7f\u7528Continuous-State Leaky Bucket Algorithm(\u9023\u7e8c\u72c0\u614b\u6c99\u6f0f\u6f14\u7b97\u6cd5)\u6216\u8005Virtual Scheduling Algorithm(\u7d30\u5305\u865b\u64ec\u6392\u7a0b\u6f14\u7b97\u6cd5)
…………………………………….
ATM Signaling(\u8a0a\u865f),\u9023\u7dda\u8cc7\u8a0a\u7684\u5354\u8abf\u66f4\u65b0
ATM\u7528\u5916\u983b(\u8a0a\u865f\u5206\u5167\u983bin-band,\u8a0a\u865f\u548c\u8cc7\u6599\u5728\u540c\u4e00\u9023\u7dda,\u8207\u5916\u983bout-of-band,\u8a0a\u865f\u7528\u5c08\u5c6c\u983b\u9053\uff09
\u7528\u9014\uff1a(1)ATM\u9023\u7dda\u7684\u5efa\u7acb\u3001\u7dad\u8b77\u8207\u91cb\u653e(2)\u8a0a\u52d9\u53c3\u6578\u7684\u50b3\u8f38\u8207\u5354\u8abf(\u8a0a\u52d9\u63a7\u5236traffic control\u8207\u58c5\u585e\u63a7\u5236congestion control)
\u4fdd\u7559\u7d66\u8a0a\u865f\u4f7f\u7528\u7684VPI\/VCI\u53ebsignaling virtual channel(\u8a0a\u865f\u865b\u64ec\u901a\u9053),\u6709\u56db\u7a2e\uff1a
Meta-signaling(\u5f8c\u8a0a\u865f)\uff1a\u7528\u4f86\u7ba1\u7406\u8a0a\u865f\u865b\u64ec\u901a\u9053\u7684\u5efa\u7acb\u3001\u7dad\u8b77\u8207\u91cb\u653e\u3002\u6b64\u7a2e\u901a\u9053\u662f\u96d9\u5411\u7684\u4e14\u6c38\u4e45\u5b58\u5728\u3002
Point-to-Point(\u9ede\u5c0d\u9ede)\uff1a\u7528\u4f86\u5efa\u7acb\u3001\u7dad\u8b77\u8207\u91cb\u653e\u50b3\u8f38\u4f7f\u7528\u8005\u8cc7\u6599\u7684\u901a\u9053\uff0c\u901a\u9053\u662f\u96d9\u5411\u7684\u4f46\u4e0d\u662f\u6c38\u4e45\u5b58\u5728\u3002
\u6b64\u7a2e\u8a0a\u865f\u865b\u64ec\u901a\u9053\u53ea\u6709\u7576\u4f7f\u7528\u8005\u60f3\u50b3\u8f38\u8cc7\u6599\u6642\uff0c\u624d\u88ab\u914d\u7f6e\u51fa\u4f86\u4f7f\u7528\u3002
General broadcast(\u4e00\u822c\u5ee3\u64ad)\uff1a\u7528\u4f86\u5c07\u8a0a\u865f\u50b3\u9001\u7d66\u7db2\u8def\u4e2d\u7684\u6bcf\u4e00\u500b\u7bc0\u9ede\uff0c\u662f\u5c6c\u65bc\u55ae\u5411\u7684\uff0c\u4e14\u5176\u65b9\u5411\u662f\u7531\u7db2\u8def\u5230\u5404\u500b\u7bc0\u9ede\u3002
Selective broadcast(\u9078\u64c7\u6027\u5ee3\u64ad)\uff1a\u7528\u4f86\u5c07\u8a0a\u865f\u9001\u7d66\u67d0\u4e9b\u7bc0\u9ede\uff0c\u9019\u4e9b\u7bc0\u9ede\u5177\u6709\u67d0\u4e9b\u76f8\u540c\u7684\u6027\u8cea\u3002\u5c6c\u65bc\u55ae\u5411\uff0c\u65b9\u5411\u662f\u7531\u7db2\u8def\u5230\u5404\u500b\u7bc0\u9ede\u3002<\/p>\n\n\n\n
B-ISUP(Broadband Interim Signaling User Protocol,\u5bec\u983b\u9593\u6b47\u8a0a\u865f\u4f7f\u7528\u8005\u5354\u5b9a):ITU-T\u5236\u8a02\u3002
\u4e5f\u5c31\u662fATM\u7db2\u8def\u4e2d\u7684SS7(Signaling System 7,\u7b2c\u4e03\u8a0a\u865f\u7cfb\u7d71)
Q.2931:\u662fQ.931\u7684ITU-T\u6539\u826fQ.93B\uff0c\u5728\u7d93\u904e\u6a19\u6e96\u5316
ATM FORUM\u6240\u5236\u8a02\u51fa\u4f86\u7684\u8a0a\u865f\u5354\u5b9a:\u6b64\u5354\u5b9a\u53ea\u662fQ.93B\u4e2d\u7684\u4e00\u90e8\u4efd\u3002ATM FORUM\u6700\u5f8c\u5c07\u5176\u5236\u8a02\u70ba\u4e00\u6a19\u6e96\uff0c\u4e14\u8207Q.2931\u76f8\u5bb9\u3002<\/p>\n\n\n\n
\u4e3b\u8981\u5229\u7528CPCS(Common Part Convergence Sublayer,\u5171\u540c\u532f\u96c6\u6b21\u5c64)\u4e2d\u7684SSCOP(Service Specific Connection-Oriented Protocol,\u7279\u5b9a\u670d\u52d9\u9023\u7d50\u5c0e\u5411\u901a\u8a0a\u5354\u5b9a)\u4f86\u63d0\u4f9b\u53ef\u9760\u7684\u8a0a\u865f\u50b3\u8f38\u670d\u52d9\uff0c\u800c\u5728\u7279\u5b9a\u670d\u52d9\u9023\u7d50\u5c0e\u5411\u901a\u8a0a\u5354\u5b9a\u4e0a\uff0c\u5c0dUNI\u548cNNI\u7686\u6709\u63d0\u4f9bSSCF(Specific Service Coordination Function,\u7279\u5b9a\u670d\u52d9\u5354\u8abf\u529f\u80fd)
………………………..<\/p>\n\n\n\n
backbone approach(\u9aa8\u5e79\u5f0f):ATM\u7db2\u8def\u626e\u6f14\u50b3\u7d71\u5340\u7db2\u4e92\u901a\u6642\u7684\u9aa8\u5e79\u89d2\u8272
\u7d93\u6a4b\u63a5\u5668\u5728\u4e0d\u540c\u5340\u7db2\u4e0a\u7684\u5de5\u4f5c\u7ad9\u53ef\u900f\u904eATM\u7db2\u8def\u4e92\u901a
\u5df2\u958b\u767c\u8edf\u9ad4\u4ecd\u5728\u50b3\u7d71\u5340\u7db2\u57f7\u884c\uff0c\u4e0d\u9808\u505a\u4efb\u4f55\u4fee\u6539,\u65b9\u6cd5\u7c21\u55ae
\u7f3a\u9ede\uff1a\u9700\u8f03\u591a\u983b\u5bec\u7684\u4f3a\u670d\u5668\u4ecd\u7559\u5728\u50b3\u7d71\u5340\u7db2\u4e0a\uff0c\u983b\u5bec\u4e0d\u8db3\u554f\u984c\u4ecd\u5728
\u7d9c\u5408\u5f0f\u9023\u7d50:\u5de5\u4f5c\u7ad9\u53ef\u76f4\u63a5\u9023ATM\u7db2\u8def,\u50b3\u7d71\u5340\u7db2\u8207ATM\u7db2\u9593\u4f7f\u7528\u8def\u5f91\u5668\u6216\u6a4b\u63a5\u5668\u9023\u7d50
\u76f4\u63a5\u9023\u4e0aATM\u7db2\u8def\u7684\u5de5\u4f5c\u7ad9(\u5982\u4f3a\u670d\u5668)\u53ef\u4eab\u53d7\u5230ATM\u7db2\u8def\u63d0\u4f9b\u4e4b\u5927\u91cf\u4e14\u5c08\u5c6c\u7684\u983b\u5bec
\u4f4d\u65bc\u50b3\u7d71\u7db2\u8def\u4e0a\u7684clients\u5247\u53ef\u4ee5\u7d93\u7531\u8def\u5f91\u5668\u8207\u4f3a\u670d\u5668\u901a\u8a0a
\u7f3a\u9ede:\u61c9\u7528\u8edf\u9ad4\u53ef\u80fd\u5fc5\u9808\u4fee\u6539\u754c\u9762\u7a0b\u5f0f\u624d\u80fd\u9023\u4e0aATM\u7db2\u8def(\u56e0\u4e0b\u5c64\u8b8a\u6210ATM\u901a\u8a0a\u5354\u5b9a)<\/p>\n\n\n\n
address resolution(\u4f4d\u5740\u8f49\u63db):\u5efa\u9023\u7dda\u5f97\u77e5\u9053\u5de5\u4f5c\u7ad9(\u6216\u8def\u5f91\u5668,\u6a4b\u63a5\u5668)\u7684ATM\u4f4d\u5740,
\u8def\u7531\u5668\u6709\u7db2\u8def\u5c64\u4f4d\u5740(\u5982IP,IPX\u7b49\u7b49)\u8f49\u6210ATM\u4f4d\u5740\u7684\u554f\u984c
\u6a4b\u63a5\u5668\u6709\u5c07MAC\u4f4d\u5740\u8f49\u6210ATM\u4f4d\u5740\u7684\u554f\u984c
broadcast\/multicast(\u5ee3\u64ad\/\u7fa4\u64ad):\u8def\u5f91\u5668,\u6a4b\u63a5\u5668\u4e26\u4e0d\u904e\u6ffe\u7db2\u8def\u5c64\u4e4b\u5ee3\u64ad\u6216\u7fa4\u64ad\u5c01\u5305,
\u727d\u6d89\u5230\u5982\u4f55\u5efa\u7acb\u5177\u5ee3\u64ad\u6027\u8cea\u7684\u9023\u7dda<\/p>\n\n\n\n
1995\u5e74ATM\u8ad6\u58c7\u63d0\u51faLANE(Local Area Network Emulation,\u5340\u57df\u7db2\u8def\u6a21\u64ec)
ATM\u7db2\u8def\u5fc5\u9808\u63d0\u4f9b\u5177\u6709\u6a21\u4eff(\u5982 Ethernet, Token-ring, FDDI \u7b49\u7b49)\u901a\u8a0a\u5354\u5b9a\u529f\u80fd\u7684\u8edf\u9ad4
\u4f7f\u50b3\u7d71\u5340\u7db2\u4e0a\u57f7\u884c\u7684\u61c9\u7528\u8edf\u9ad4\u79fb\u690d\u5230ATM\u7db2\u8def\u4e0a\u7684\u5de5\u4f5c\u7ad9\u6642\u4ecd\u53ef\u4ee5\u57f7\u884c\u800c\u4e0d\u5fc5\u77e5\u9053ATM\u7db2\u8def\u7684\u5b58\u5728<\/p>\n\n\n\n
LES(LANE Server,\u5340\u57df\u7db2\u8def\u6a21\u64ec\u4f3a\u670d\u5668),\u4e3b\u8981\u529f\u80fd\u5c31\u662f\u9032\u884cMAC-to-ATM\u7684\u5730\u5740\u8f49\u63db
LECS(LAN Configuration Server,\u5340\u57df\u7db2\u8def\u7d44\u614b\u4f3a\u670d\u5668)
BUS(Broadcast and Unknown Server,\u5ee3\u64ad\u4f3a\u670d\u5668)
ELAN(emulated LAN,\u6a21\u64ec\u5340\u57df\u7db2\u8def),ATM LAN Emulation\u5354\u5b9a\u4e2d\u5fc5\u5099\u7684\u6280\u8853<\/p>\n","protected":false},"excerpt":{"rendered":"