Page of 428
Download Table of ContentsContents Print This PagePrint Bookmark
   
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428

Advertisement

Figure 20 Network diagram for inter-AS option B
In terms of scalability, inter-AS option B is better than option A.
When adopting the MP-EBGP method, note the following:
ASBRs perform no route target filtering on VPN-IPv4 routes that they receive from each other.
Therefore, the ISPs in different ASs that exchange VPN-IPv4 routes must agree on the route
exchange.
VPN-IPv4 routes are exchanged only between VPN peers. A VPN user can exchange VPN-IPv4
routes neither with the public network nor with MP-EBGP peers with whom it has not reached
agreement on the route exchange.
Inter-AS option C
The Inter-AS option A and option B solutions can satisfy the needs for inter-AS VPNs. However, they
require that the ASBRs maintain and advertise VPN-IPv4 routes. When every AS needs to exchange a
great amount of VPN routes, the ASBRs may become bottlenecks hindering network extension.
One way to solve the problem is to make PEs directly exchange VPN-IPv4 routes without the participation
of ASBRs:
Two ASBRs advertise labeled IPv4 routes to PEs in their respective ASs through MP-IBGP.
The ASBRs neither maintain VPN-IPv4 routes nor advertise VPN-IPv4 routes to each other.
An ASBR maintains labeled IPv4 routes of the PEs in the AS and advertises them to the peers in the
other ASs. The ASBR of another AS also advertises labeled IPv4 routes. Thus, an LSP is established
between the ingress PE and egress PE.
Between PEs of different ASs, Multi-hop EBGP connections are established to exchange VPN-IPv4
routes.
238

Advertisement

   Related Manuals for HP 10500 SERIES

Comments to this Manuals

Symbols: 0
Latest comments: