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, available at 17 <https://ppp.samba.org>. Make sure that you have the version of pppd 18 recommended in <file:Documentation/Changes>. 19 The PPP option enlarges your kernel by about 16 KB. 20 21 There are actually two versions of PPP: the traditional PPP for 22 asynchronous lines, such as regular analog phone lines, and 23 synchronous PPP which can be used over digital ISDN lines for 24 example. If you want to use PPP over phone lines or other 25 asynchronous serial lines, you need to say Y (or M) here and also to 26 the next option, "PPP support for async serial ports". For PPP over 27 synchronous lines, you should say Y (or M) here and to "Support 28 synchronous PPP", below. 29 30 If you said Y to "Version information on all symbols" above, then 31 you cannot compile the PPP driver into the kernel; you can then only 32 compile it as a module. To compile this driver as a module, choose M 33 here. The module will be called ppp_generic. 34 35if PPP 36 37config PPP_BSDCOMP 38 tristate "PPP BSD-Compress compression" 39 help 40 Support for the BSD-Compress compression method for PPP, which uses 41 the LZW compression method to compress each PPP packet before it is 42 sent over the wire. The machine at the other end of the PPP link 43 (usually your ISP) has to support the BSD-Compress compression 44 method as well for this to be useful. Even if they don't support it, 45 it is safe to say Y here. 46 47 The PPP Deflate compression method ("PPP Deflate compression", 48 above) is preferable to BSD-Compress, because it compresses better 49 and is patent-free. 50 51 Note that the BSD compression code will always be compiled as a 52 module; it is called bsd_comp and will show up in the directory 53 modules once you have said "make modules". If unsure, say N. 54 55config PPP_DEFLATE 56 tristate "PPP Deflate compression" 57 select ZLIB_INFLATE 58 select ZLIB_DEFLATE 59 help 60 Support for the Deflate compression method for PPP, which uses the 61 Deflate algorithm (the same algorithm that gzip uses) to compress 62 each PPP packet before it is sent over the wire. The machine at the 63 other end of the PPP link (usually your ISP) has to support the 64 Deflate compression method as well for this to be useful. Even if 65 they don't support it, it is safe to say Y here. 66 67 To compile this driver as a module, choose M here. 68 69config PPP_FILTER 70 bool "PPP filtering" 71 help 72 Say Y here if you want to be able to filter the packets passing over 73 PPP interfaces. This allows you to control which packets count as 74 activity (i.e. which packets will reset the idle timer or bring up 75 a demand-dialed link) and which packets are to be dropped entirely. 76 You need to say Y here if you wish to use the pass-filter and 77 active-filter options to pppd. 78 79 If unsure, say N. 80 81config PPP_MPPE 82 tristate "PPP MPPE compression (encryption)" 83 select CRYPTO_LIB_ARC4 84 select CRYPTO_LIB_SHA1 85 help 86 Support for the MPPE Encryption protocol, as employed by the 87 Microsoft Point-to-Point Tunneling Protocol. 88 89 See http://pptpclient.sourceforge.net/ for information on 90 configuring PPTP clients and servers to utilize this method. 91 92config PPP_MULTILINK 93 bool "PPP multilink support" 94 help 95 PPP multilink is a protocol (defined in RFC 1990) which allows you 96 to combine several (logical or physical) lines into one logical PPP 97 connection, so that you can utilize your full bandwidth. 98 99 This has to be supported at the other end as well and you need a 100 version of the pppd daemon which understands the multilink protocol. 101 102 If unsure, say N. 103 104config PPPOATM 105 tristate "PPP over ATM" 106 depends on ATM 107 help 108 Support PPP (Point to Point Protocol) encapsulated in ATM frames. 109 This implementation does not yet comply with section 8 of RFC2364, 110 which can lead to bad results if the ATM peer loses state and 111 changes its encapsulation unilaterally. 112 113config PPPOX 114 tristate 115 116config PPPOE 117 tristate "PPP over Ethernet" 118 select PPPOX 119 help 120 Support for PPP over Ethernet. 121 122 To work in client mode, pppd version 2.4.2 or later is required. 123 To work in server mode, the pppoe-server command from the RP-PPPoE 124 package is also required, available at 125 <https://dianne.skoll.ca/projects/rp-pppoe/>. 126 127choice 128 prompt "Number of PPPoE hash bits" 129 default PPPOE_HASH_BITS_4 130 depends on PPPOE 131 help 132 Select the number of bits used for hashing PPPoE interfaces. 133 134 Larger sizes reduces the risk of hash collisions at the cost 135 of slightly increased memory usage. 136 137 This hash table is on a per outer ethernet interface. 138 139config PPPOE_HASH_BITS_1 140 bool "1 bit (2 buckets)" 141 142config PPPOE_HASH_BITS_2 143 bool "2 bits (4 buckets)" 144 145config PPPOE_HASH_BITS_4 146 bool "4 bits (16 buckets)" 147 148config PPPOE_HASH_BITS_8 149 bool "8 bits (256 buckets)" 150 151endchoice 152 153config PPPOE_HASH_BITS 154 int 155 default 1 if PPPOE_HASH_BITS_1 156 default 2 if PPPOE_HASH_BITS_2 157 default 4 if PPPOE_HASH_BITS_4 158 default 8 if PPPOE_HASH_BITS_8 159 default 4 160 161config PPTP 162 tristate "PPP over IPv4 (PPTP)" 163 depends on NET_IPGRE_DEMUX 164 select PPPOX 165 help 166 Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) 167 168 This driver requires pppd plugin to work in client mode or 169 modified pptpd (poptop) to work in server mode. 170 See http://accel-pptp.sourceforge.net/ for information how to 171 utilize this module. 172 173config PPPOL2TP 174 tristate "PPP over L2TP" 175 depends on L2TP 176 select PPPOX 177 help 178 Support for PPP-over-L2TP socket family. L2TP is a protocol 179 used by ISPs and enterprises to tunnel PPP traffic over UDP 180 tunnels. L2TP is replacing PPTP for VPN uses. 181if TTY 182 183config PPP_ASYNC 184 tristate "PPP support for async serial ports" 185 select CRC_CCITT 186 help 187 Say Y (or M) here if you want to be able to use PPP over standard 188 asynchronous serial ports, such as COM1 or COM2 on a PC. If you use 189 a modem (not a synchronous or ISDN modem) to contact your ISP, you 190 need this option. 191 192 To compile this driver as a module, choose M here. 193 194 If unsure, say Y. 195 196config PPP_SYNC_TTY 197 tristate "PPP support for sync tty ports" 198 help 199 Say Y (or M) here if you want to be able to use PPP over synchronous 200 (HDLC) tty devices, such as the SyncLink adapter. These devices 201 are often used for high-speed leased lines like T1/E1. 202 203 To compile this driver as a module, choose M here. 204 205endif # TTY 206 207endif # PPP 208