Symantecâ¢ Security Gateways Reference Guide - Sawmill

More documents

Recommendations

Info

66 Understanding accessRulesWhen a connection request matches a rule, the security gateway determines whether or not authenticationon that rule is required. If the rule requires authentication and the connecting user identifies themselfproperly, the connection is permitted. If the user fails to identify themself, the connection is denied, and amessage is logged.Configuration and modification information for rules is found in your product’s administrator guide.
Chapter 5Controlling service accessThis chapter includes the following topics:■■FiltersContent filteringFiltersFilters let the administrator discard packets that should not be forwarded or serviced locally. A wellconstructedfilter can reduce a significant portion of undesired traffic, freeing up valuable resources toaddress legitimate connections. Packet filtering is a versatile security gateway feature that is sometimesconsidered complicated because packet filters are order-dependent and use different logic fromauthorization rules, which are based on best fit. Make sure you understand how packet filters work andhow to use them before creating any filters.Understanding filtersA filter is a criteria list and action pairing that consists of the following information:■■■■■■■■The IP address and netmask of the source.The IP address and netmask of the destination.The type of protocol.The lower bound of the source port (if applicable).The upper bound of the source port (if applicable).The lower bound of the destination port (if applicable).The upper bound of the destination port (if applicable).Any protocol-related flags (such as TCP ACK).Each packet is checked against the criteria list to see if there is a match. If the packet matches, the pairedaction takes place; the action either allows or denies the packet. An allow filter sends the packet up thestack to be processed by the proxies. If the packet does not match, or it matches but the action is deny, thepacket is dropped.A filter is processed sequentially until a match is found. It is important to understand that the filteringmechanism only looks for the first matching entry and takes that action; the order of deny and allowactions is significant. Filters are not like rules, where all rules are considered when making a decision toallow or deny. In general, put the most specific filter elements first and more general elements last.Note: With no filter list in place, all packets are allowed by default. If a filter is added to the list, the defaultpolicy changes to deny anything not specifically allowed by the filter. Any packet that fails to match isdropped. For this reason, filters must be constructed with care.
Page 1 and 2:
Symantec Security GatewaysReference
Page 3:
Licensing and registrationContactin
Page 6 and 7:
6 ContentsMail server record ......
Page 8 and 9:
8 ContentsChapter 9Chapter 10Append
Page 10 and 11:
10 Contents
Page 12 and 13:
12 Introducing Symantec security ga
Page 14 and 15:
14 Introducing Symantec security ga
Page 16 and 17: 16 Network security overviewSecurit
Page 24 and 25: 24 Network security overviewManagem
Page 32 and 33: 32 Security gateway fundamentalsRou
Page 38 and 39: 38 Security gateway fundamentalsDom
Page 44 and 45: 44 Understanding accessNetwork prot
Page 46 and 47: 46 Understanding accessNetwork prot
Page 48 and 49: 48 Understanding accessProxiesProxi
Page 50 and 51: 50 Understanding accessProxiesExamp
Page 52 and 53: 52 Understanding accessProxiesThe D
Page 54 and 55: 54 Understanding accessProxiesThe H
Page 56 and 57: 56 Understanding accessProxiesThe N
Page 58 and 59: 58 Understanding accessProxiesThe S
Page 60 and 61: 60 Understanding accessProxiesTable
Page 62 and 63: 62 Understanding accessService grou
Page 64 and 65: 64 Understanding accessRulesTable 4
Page 68 and 69: 68 Controlling service accessFilter
Page 70 and 71: 70 Controlling service accessFilter
Page 72 and 73: 72 Controlling service accessConten
Page 78 and 79: 78 Controlling user accessAuthentic
Page 86 and 87: 86 Controlling user accessTime Peri
Page 88 and 89: 88 Understanding VPN tunnelsTunnels
Page 90 and 91: 90 Understanding VPN tunnelsTunnels
Page 92 and 93: 92 Understanding VPN tunnelsIPsec s
Page 100 and 101: 100 Understanding VPN tunnelsGlobal
Page 102 and 103: 102 Monitoring security gateway tra
Page 114 and 115: 114 Preventing attacksAntivirus (ap
Page 116 and 117:
116 Preventing attacksIntrusion det
Page 118 and 119:
118 Preventing attacksLogical netwo
Page 120 and 121:
120 Preventing attacksAddress trans
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
126 Preventing attacksAnti-spam mea
Page 128 and 129:
128 Ensuring availabilitySymantec
Page 130 and 131:
130 Ensuring availabilityStateful f
Page 132 and 133:
132 Ensuring availabilityCluster ad
Page 134 and 135:
134 Log messagesInformational messa
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Page 144 and 145:
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
158 Log messagesNotice messages (20
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
176 Log messagesWarning messages (3
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
Page 186 and 187:
Page 188 and 189:
Page 190 and 191:
Page 192 and 193:
Page 194 and 195:
Page 196 and 197:
Page 198 and 199:
Page 200 and 201:
Page 202 and 203:
Page 204 and 205:
Page 206 and 207:
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
Page 228 and 229:
Page 230 and 231:
230 Log messagesError messages (400
Page 232 and 233:
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
Page 240 and 241:
Page 242 and 243:
Page 244 and 245:
Page 246 and 247:
Page 248 and 249:
Page 250 and 251:
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
256 Log messagesAlert messages (500
Page 258 and 259:
258 Log messagesAlert messages (500
Page 260 and 261:
260 Log messagesCritical messages (
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
270 Log messagesEmergency messages
Page 272 and 273:
272 Log messagesEmergency messages
Page 274 and 275:
274 IDS eventsAbout IDS/IPS events
Page 276 and 277:
Page 278 and 279:
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
Page 296 and 297:
296 IDS eventsDenial-of-ServiceTabl
Page 298 and 299:
298 IDS eventsDenial-of-ServiceResp
Page 300 and 301:
300 IDS eventsDenial-of-ServiceMalf
Page 302 and 303:
302 IDS eventsIntrusion attemptsUnk
Page 304 and 305:
304 IDS eventsIntrusion attemptsCod
Page 306 and 307:
306 IDS eventsIntrusion attemptsDNS
Page 308 and 309:
308 IDS eventsIntrusion attemptsAff
Page 310 and 311:
Page 312 and 313:
312 IDS eventsIntrusion attemptsFTP
Page 314 and 315:
314 IDS eventsIntrusion attemptsHTT
Page 316 and 317:
Page 318 and 319:
Page 320 and 321:
320 IDS eventsIntrusion attemptsIMA
Page 322 and 323:
322 IDS eventsIntrusion attemptsIRC
Page 324 and 325:
324 IDS eventsIntrusion attemptsIRC
Page 326 and 327:
Page 328 and 329:
328 IDS eventsIntrusion attemptsNim
Page 330 and 331:
330 IDS eventsIntrusion attemptsNim
Page 332 and 333:
332 IDS eventsIntrusion attemptsOSP
Page 334 and 335:
334 IDS eventsIntrusion attemptsRlo
Page 336 and 337:
Page 338 and 339:
Page 340 and 341:
Page 342 and 343:
342 IDS eventsIntrusion attemptsSta
Page 344 and 345:
Page 346 and 347:
Page 348 and 349:
Page 350 and 351:
Page 352 and 353:
352 IDS eventsIntrusion attemptsWAR
Page 354 and 355:
354 IDS eventsProbesSensor Record F
Page 356 and 357:
356 IDS eventsProbesAffected:No spe
Page 358 and 359:
358 IDS eventsSignaturesSMTP Probin
Page 360 and 361:
360 IDS eventsSignaturesHTTP IIS IS
Page 362 and 363:
362 IDS eventsSignaturesAffected: A
Page 364 and 365:
364 IDS eventsSuspicious activitySu
Page 366 and 367:
366 IDS eventsSuspicious activityBG
Page 368 and 369:
368 IDS eventsSuspicious activityBG
Page 370 and 371:
370 IDS eventsSuspicious activityDN
Page 372 and 373:
372 IDS eventsSuspicious activityFT
Page 374 and 375:
374 IDS eventsSuspicious activityAf
Page 376 and 377:
Page 378 and 379:
378 IDS eventsSuspicious activityHT
Page 380 and 381:
Page 382 and 383:
Page 384 and 385:
Page 386 and 387:
Page 388 and 389:
Page 390 and 391:
Page 392 and 393:
392 IDS eventsSuspicious activityId
Page 394 and 395:
394 IDS eventsSuspicious activityIM
Page 396 and 397:
Page 398 and 399:
Page 400 and 401:
Page 402 and 403:
Page 404 and 405:
404 IDS eventsSuspicious activityMa
Page 406 and 407:
Page 408 and 409:
Page 410 and 411:
Page 412 and 413:
Page 414 and 415:
Page 416 and 417:
Page 418 and 419:
Page 420 and 421:
Page 422 and 423:
Page 424 and 425:
Page 426 and 427:
Page 428 and 429:
Page 430 and 431:
Page 432 and 433:
Page 434 and 435:
Page 436 and 437:
Page 438 and 439:
Page 440 and 441:
Page 442 and 443:
442 IDS eventsSuspicious activityNN
Page 444 and 445:
444 IDS eventsSuspicious activityOS
Page 446 and 447:
446 IDS eventsSuspicious activityOS
Page 448 and 449:
448 IDS eventsSuspicious activityPO
Page 450 and 451:
450 IDS eventsSuspicious activityRl
Page 452 and 453:
452 IDS eventsSuspicious activityRP
Page 454 and 455:
454 IDS eventsSuspicious activityRe
Page 456 and 457:
Page 458 and 459:
458 IDS eventsSuspicious activitySM
Page 460 and 461:
460 IDS eventsSuspicious activitySN
Page 462 and 463:
462 IDS eventsSuspicious activitySO
Page 464 and 465:
Page 466 and 467:
Page 468 and 469:
Page 470 and 471:
Page 472 and 473:
Page 474 and 475:
Page 476 and 477:
Page 478 and 479:
Page 480 and 481:
Page 482 and 483:
Page 484 and 485:
Page 486 and 487:
Page 488 and 489:
Page 490 and 491:
Page 492 and 493:
Page 494 and 495:
Page 496 and 497:
Page 498 and 499:
Page 500 and 501:
Page 502 and 503:
Page 504 and 505:
Page 506 and 507:
Page 508 and 509:
508 IDS eventsSuspicious activity
Page 510 and 511:
510 IndexIP address spoofing 21Man-
Page 512 and 513:
512 IndexHH.323alias report 105prox
Page 514 and 515:
514 IndexRTSP 57service parameters
Page 516:
516 Index
show all

Symantecâ¢ Security Gateways Reference Guide - Sawmill

Create successful ePaper yourself

Delete template?

Save as template?

Symantecâ¢ Security Gateways Reference Guide - Sawmill