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 89 select CRYPTO_SHA1 90 select CRYPTO_LIB_ARC4 91 help 92 Support for the MPPE Encryption protocol, as employed by the 93 Microsoft Point-to-Point Tunneling Protocol. 94 95 See http://pptpclient.sourceforge.net/ for information on 96 configuring PPTP clients and servers to utilize this method. 97 98config PPP_MULTILINK 99 bool "PPP multilink support" 100 depends on PPP 101 help 102 PPP multilink is a protocol (defined in RFC 1990) which allows you 103 to combine several (logical or physical) lines into one logical PPP 104 connection, so that you can utilize your full bandwidth. 105 106 This has to be supported at the other end as well and you need a 107 version of the pppd daemon which understands the multilink protocol. 108 109 If unsure, say N. 110 111config PPPOATM 112 tristate "PPP over ATM" 113 depends on ATM && PPP 114 help 115 Support PPP (Point to Point Protocol) encapsulated in ATM frames. 116 This implementation does not yet comply with section 8 of RFC2364, 117 which can lead to bad results if the ATM peer loses state and 118 changes its encapsulation unilaterally. 119 120config PPPOE 121 tristate "PPP over Ethernet" 122 depends on PPP 123 help 124 Support for PPP over Ethernet. 125 126 This driver requires the latest version of pppd from the CVS 127 repository at cvs.samba.org. Alternatively, see the 128 RoaringPenguin package (<http://www.roaringpenguin.com/pppoe>) 129 which contains instruction on how to use this driver (under 130 the heading "Kernel mode PPPoE"). 131 132choice 133 prompt "Number of PPPoE hash bits" 134 default PPPOE_HASH_BITS_4 135 depends on PPPOE 136 help 137 Select the number of bits used for hashing PPPoE interfaces. 138 139 Larger sizes reduces the risk of hash collisions at the cost 140 of slightly increased memory usage. 141 142 This hash table is on a per outer ethernet interface. 143 144config PPPOE_HASH_BITS_1 145 bool "1 bit (2 buckets)" 146 147config PPPOE_HASH_BITS_2 148 bool "2 bits (4 buckets)" 149 150config PPPOE_HASH_BITS_4 151 bool "4 bits (16 buckets)" 152 153config PPPOE_HASH_BITS_8 154 bool "8 bits (256 buckets)" 155 156endchoice 157 158config PPPOE_HASH_BITS 159 int 160 default 1 if PPPOE_HASH_BITS_1 161 default 2 if PPPOE_HASH_BITS_2 162 default 4 if PPPOE_HASH_BITS_4 163 default 8 if PPPOE_HASH_BITS_8 164 default 4 165 166config PPTP 167 tristate "PPP over IPv4 (PPTP)" 168 depends on PPP && NET_IPGRE_DEMUX 169 help 170 Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) 171 172 This driver requires pppd plugin to work in client mode or 173 modified pptpd (poptop) to work in server mode. 174 See http://accel-pptp.sourceforge.net/ for information how to 175 utilize this module. 176 177config PPPOL2TP 178 tristate "PPP over L2TP" 179 depends on L2TP && PPP 180 help 181 Support for PPP-over-L2TP socket family. L2TP is a protocol 182 used by ISPs and enterprises to tunnel PPP traffic over UDP 183 tunnels. L2TP is replacing PPTP for VPN uses. 184if TTY 185 186config PPP_ASYNC 187 tristate "PPP support for async serial ports" 188 depends on PPP 189 select CRC_CCITT 190 help 191 Say Y (or M) here if you want to be able to use PPP over standard 192 asynchronous serial ports, such as COM1 or COM2 on a PC. If you use 193 a modem (not a synchronous or ISDN modem) to contact your ISP, you 194 need this option. 195 196 To compile this driver as a module, choose M here. 197 198 If unsure, say Y. 199 200config PPP_SYNC_TTY 201 tristate "PPP support for sync tty ports" 202 depends on PPP 203 help 204 Say Y (or M) here if you want to be able to use PPP over synchronous 205 (HDLC) tty devices, such as the SyncLink adapter. These devices 206 are often used for high-speed leased lines like T1/E1. 207 208 To compile this driver as a module, choose M here. 209 210endif # TTY 211 212endif # PPP 213