1# SPDX-License-Identifier: GPL-2.0-only 2# 3# PPP network device configuration 4# 5 6config PPP 7 tristate "PPP (point-to-point protocol) support" 8 select SLHC 9 help 10 PPP (Point to Point Protocol) is a newer and better SLIP. It serves 11 the same purpose: sending Internet traffic over telephone (and other 12 serial) lines. Ask your access provider if they support it, because 13 otherwise you can't use it; most Internet access providers these 14 days support PPP rather than SLIP. 15 16 To use PPP, you need an additional program called pppd as described 17 in the PPP-HOWTO, available at 18 <http://www.tldp.org/docs.html#howto>. Make sure that you have 19 the version of pppd recommended in <file:Documentation/Changes>. 20 The PPP option enlarges your kernel by about 16 KB. 21 22 There are actually two versions of PPP: the traditional PPP for 23 asynchronous lines, such as regular analog phone lines, and 24 synchronous PPP which can be used over digital ISDN lines for 25 example. If you want to use PPP over phone lines or other 26 asynchronous serial lines, you need to say Y (or M) here and also to 27 the next option, "PPP support for async serial ports". For PPP over 28 synchronous lines, you should say Y (or M) here and to "Support 29 synchronous PPP", below. 30 31 If you said Y to "Version information on all symbols" above, then 32 you cannot compile the PPP driver into the kernel; you can then only 33 compile it as a module. To compile this driver as a module, choose M 34 here. The module will be called ppp_generic. 35 36if PPP 37 38config PPP_BSDCOMP 39 tristate "PPP BSD-Compress compression" 40 depends on PPP 41 help 42 Support for the BSD-Compress compression method for PPP, which uses 43 the LZW compression method to compress each PPP packet before it is 44 sent over the wire. The machine at the other end of the PPP link 45 (usually your ISP) has to support the BSD-Compress compression 46 method as well for this to be useful. Even if they don't support it, 47 it is safe to say Y here. 48 49 The PPP Deflate compression method ("PPP Deflate compression", 50 above) is preferable to BSD-Compress, because it compresses better 51 and is patent-free. 52 53 Note that the BSD compression code will always be compiled as a 54 module; it is called bsd_comp and will show up in the directory 55 modules once you have said "make modules". If unsure, say N. 56 57config PPP_DEFLATE 58 tristate "PPP Deflate compression" 59 depends on PPP 60 select ZLIB_INFLATE 61 select ZLIB_DEFLATE 62 help 63 Support for the Deflate compression method for PPP, which uses the 64 Deflate algorithm (the same algorithm that gzip uses) to compress 65 each PPP packet before it is sent over the wire. The machine at the 66 other end of the PPP link (usually your ISP) has to support the 67 Deflate compression method as well for this to be useful. Even if 68 they don't support it, it is safe to say Y here. 69 70 To compile this driver as a module, choose M here. 71 72config PPP_FILTER 73 bool "PPP filtering" 74 depends on PPP 75 help 76 Say Y here if you want to be able to filter the packets passing over 77 PPP interfaces. This allows you to control which packets count as 78 activity (i.e. which packets will reset the idle timer or bring up 79 a demand-dialed link) and which packets are to be dropped entirely. 80 You need to say Y here if you wish to use the pass-filter and 81 active-filter options to pppd. 82 83 If unsure, say N. 84 85config PPP_MPPE 86 tristate "PPP MPPE compression (encryption)" 87 depends on PPP 88 select CRYPTO_LIB_ARC4 89 select CRYPTO_LIB_SHA1 90 help 91 Support for the MPPE Encryption protocol, as employed by the 92 Microsoft Point-to-Point Tunneling Protocol. 93 94 See http://pptpclient.sourceforge.net/ for information on 95 configuring PPTP clients and servers to utilize this method. 96 97config PPP_MULTILINK 98 bool "PPP multilink support" 99 depends on PPP 100 help 101 PPP multilink is a protocol (defined in RFC 1990) which allows you 102 to combine several (logical or physical) lines into one logical PPP 103 connection, so that you can utilize your full bandwidth. 104 105 This has to be supported at the other end as well and you need a 106 version of the pppd daemon which understands the multilink protocol. 107 108 If unsure, say N. 109 110config PPPOATM 111 tristate "PPP over ATM" 112 depends on ATM && PPP 113 help 114 Support PPP (Point to Point Protocol) encapsulated in ATM frames. 115 This implementation does not yet comply with section 8 of RFC2364, 116 which can lead to bad results if the ATM peer loses state and 117 changes its encapsulation unilaterally. 118 119config PPPOE 120 tristate "PPP over Ethernet" 121 depends on PPP 122 help 123 Support for PPP over Ethernet. 124 125 This driver requires the latest version of pppd from the CVS 126 repository at cvs.samba.org. Alternatively, see the 127 RoaringPenguin package (<http://www.roaringpenguin.com/pppoe>) 128 which contains instruction on how to use this driver (under 129 the heading "Kernel mode PPPoE"). 130 131choice 132 prompt "Number of PPPoE hash bits" 133 default PPPOE_HASH_BITS_4 134 depends on PPPOE 135 help 136 Select the number of bits used for hashing PPPoE interfaces. 137 138 Larger sizes reduces the risk of hash collisions at the cost 139 of slightly increased memory usage. 140 141 This hash table is on a per outer ethernet interface. 142 143config PPPOE_HASH_BITS_1 144 bool "1 bit (2 buckets)" 145 146config PPPOE_HASH_BITS_2 147 bool "2 bits (4 buckets)" 148 149config PPPOE_HASH_BITS_4 150 bool "4 bits (16 buckets)" 151 152config PPPOE_HASH_BITS_8 153 bool "8 bits (256 buckets)" 154 155endchoice 156 157config PPPOE_HASH_BITS 158 int 159 default 1 if PPPOE_HASH_BITS_1 160 default 2 if PPPOE_HASH_BITS_2 161 default 4 if PPPOE_HASH_BITS_4 162 default 8 if PPPOE_HASH_BITS_8 163 default 4 164 165config PPTP 166 tristate "PPP over IPv4 (PPTP)" 167 depends on PPP && NET_IPGRE_DEMUX 168 help 169 Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) 170 171 This driver requires pppd plugin to work in client mode or 172 modified pptpd (poptop) to work in server mode. 173 See http://accel-pptp.sourceforge.net/ for information how to 174 utilize this module. 175 176config PPPOL2TP 177 tristate "PPP over L2TP" 178 depends on L2TP && PPP 179 help 180 Support for PPP-over-L2TP socket family. L2TP is a protocol 181 used by ISPs and enterprises to tunnel PPP traffic over UDP 182 tunnels. L2TP is replacing PPTP for VPN uses. 183if TTY 184 185config PPP_ASYNC 186 tristate "PPP support for async serial ports" 187 depends on PPP 188 select CRC_CCITT 189 help 190 Say Y (or M) here if you want to be able to use PPP over standard 191 asynchronous serial ports, such as COM1 or COM2 on a PC. If you use 192 a modem (not a synchronous or ISDN modem) to contact your ISP, you 193 need this option. 194 195 To compile this driver as a module, choose M here. 196 197 If unsure, say Y. 198 199config PPP_SYNC_TTY 200 tristate "PPP support for sync tty ports" 201 depends on PPP 202 help 203 Say Y (or M) here if you want to be able to use PPP over synchronous 204 (HDLC) tty devices, such as the SyncLink adapter. These devices 205 are often used for high-speed leased lines like T1/E1. 206 207 To compile this driver as a module, choose M here. 208 209endif # TTY 210 211endif # PPP 212