diff --git a/scada-common/log.lua b/scada-common/log.lua
index 8ebc987..5a839fd 100644
--- a/scada-common/log.lua
+++ b/scada-common/log.lua
@@ -20,7 +20,7 @@ local MODE = { APPEND = 0, NEW = 1 }
 
 log.MODE = MODE
 
-local logger = {
+local _log = {
     not_ready = true,
     path = "/log.txt",
     mode = MODE.APPEND,
@@ -42,36 +42,36 @@ local free_space = fs.getFreeSpace
 ---@param err_msg string|nil error message
 ---@return boolean out_of_space
 local function check_out_of_space(err_msg)
-    return (free_space(logger.path) < MIN_SPACE) or ((err_msg ~= nil) and (string.find(err_msg, OUT_OF_SPACE) ~= nil))
+    return (free_space(_log.path) < MIN_SPACE) or ((err_msg ~= nil) and (string.find(err_msg, OUT_OF_SPACE) ~= nil))
 end
 
 -- private log write function
 ---@param msg_bits any[]
-local function _log(msg_bits)
-    if logger.not_ready then return end
+local function write_log(msg_bits)
+    if _log.not_ready then return end
 
     local time_stamp = os.date(TIME_FMT)
     local stamped    = util.c(time_stamp, table.unpack(msg_bits))
 
     -- attempt to write log
     local status, result = pcall(function ()
-        logger.file.writeLine(stamped)
-        logger.file.flush()
+        _log.file.writeLine(stamped)
+        _log.file.flush()
     end)
 
     -- if we don't have space, we need to create a new log file
     if check_out_of_space() then
         -- delete the old log file before opening a new one
-        logger.file.close()
-        fs.delete(logger.path)
+        _log.file.close()
+        fs.delete(_log.path)
 
         -- re-init logger and pass dmesg_out so that it doesn't change
-        log.init(logger.path, logger.mode, logger.debug, logger.dmesg_out)
+        log.init(_log.path, _log.mode, _log.debug, _log.dmesg_out)
 
         -- log the message and recycle warning
-        logger.file.writeLine(time_stamp .. WRN_TAG .. "recycled log file")
-        logger.file.writeLine(stamped)
-        logger.file.flush()
+        _log.file.writeLine(time_stamp .. WRN_TAG .. "recycled log file")
+        _log.file.writeLine(stamped)
+        _log.file.flush()
     elseif (not status) and (result ~= nil) then
         util.println("unexpected error writing to the log file: " .. result)
     end
@@ -89,45 +89,45 @@ end
 function log.init(path, write_mode, include_debug, dmesg_redirect)
     local err_msg
 
-    logger.path = path
-    logger.mode = write_mode
-    logger.debug = include_debug
-    logger.file, err_msg = fs.open(path, util.trinary(logger.mode == MODE.APPEND, "a", "w"))
+    _log.path = path
+    _log.mode = write_mode
+    _log.debug = include_debug
+    _log.file, err_msg = fs.open(path, util.trinary(_log.mode == MODE.APPEND, "a", "w"))
 
     if dmesg_redirect then
-        logger.dmesg_out = dmesg_redirect
+        _log.dmesg_out = dmesg_redirect
     else
-        logger.dmesg_out = term.current()
+        _log.dmesg_out = term.current()
     end
 
     -- check for space issues
     local out_of_space = check_out_of_space(err_msg)
 
     -- try to handle problems
-    if logger.file == nil or out_of_space then
+    if _log.file == nil or out_of_space then
         if out_of_space then
-            if fs.exists(logger.path) then
-                fs.delete(logger.path)
+            if fs.exists(_log.path) then
+                fs.delete(_log.path)
 
-                logger.file, err_msg = fs.open(path, util.trinary(logger.mode == MODE.APPEND, "a", "w"))
+                _log.file, err_msg = fs.open(path, util.trinary(_log.mode == MODE.APPEND, "a", "w"))
 
-                if logger.file then
-                    logger.file.writeLine(os.date(TIME_FMT) .. WRN_TAG .. "init recycled log file")
-                    logger.file.flush()
+                if _log.file then
+                    _log.file.writeLine(os.date(TIME_FMT) .. WRN_TAG .. "init recycled log file")
+                    _log.file.flush()
                 else error("failed to setup the log file: " .. err_msg) end
             else error("failed to make space for the log file, please delete unused files") end
         else error("unexpected error setting up the log file: " .. err_msg) end
     end
 
-    logger.not_ready = false
+    _log.not_ready = false
 end
 
 -- close the log file handle
-function log.close() logger.file.close() end
+function log.close() _log.file.close() end
 
 -- direct dmesg output to a monitor/window
 ---@param window Window window or terminal reference
-function log.direct_dmesg(window) logger.dmesg_out = window end
+function log.direct_dmesg(window) _log.dmesg_out = window end
 
 -- dmesg style logging for boot because I like linux-y things
 ---@param msg any message
@@ -142,7 +142,7 @@ function log.dmesg(msg, tag, tag_color)
     tag = util.strval(tag or "")
 
     local t_stamp = string.format("%12.2f", os.clock())
-    local out = logger.dmesg_out
+    local out = _log.dmesg_out
 
     if out ~= nil then
         local out_w, out_h = out.getSize()
@@ -180,7 +180,7 @@ function log.dmesg(msg, tag, tag_color)
             if cur_y == out_h then
                 out.scroll(1)
                 out.setCursorPos(1, cur_y)
-                logger.dmesg_scroll_count = logger.dmesg_scroll_count + 1
+                _log.dmesg_scroll_count = _log.dmesg_scroll_count + 1
             else
                 out.setCursorPos(1, cur_y + 1)
             end
@@ -216,7 +216,7 @@ function log.dmesg(msg, tag, tag_color)
                 if cur_y == out_h then
                     out.scroll(1)
                     out.setCursorPos(1, cur_y)
-                    logger.dmesg_scroll_count = logger.dmesg_scroll_count + 1
+                    _log.dmesg_scroll_count = _log.dmesg_scroll_count + 1
                 else
                     out.setCursorPos(1, cur_y + 1)
                 end
@@ -225,9 +225,9 @@ function log.dmesg(msg, tag, tag_color)
             out.write(lines[i])
         end
 
-        logger.dmesg_restore_coord = { out.getCursorPos() }
+        _log.dmesg_restore_coord = { out.getCursorPos() }
 
-        _log{"[", t_stamp, "] [", tag, "] ", msg}
+        write_log{"[", t_stamp, "] [", tag, "] ", msg}
     end
 
     return ts_coord
@@ -241,9 +241,9 @@ end
 ---@return function update, function done
 function log.dmesg_working(msg, tag, tag_color)
     local ts_coord = log.dmesg(msg, tag, tag_color)
-    local initial_scroll = logger.dmesg_scroll_count
+    local initial_scroll = _log.dmesg_scroll_count
 
-    local out = logger.dmesg_out
+    local out = _log.dmesg_out
     local width = (ts_coord.x2 - ts_coord.x1) + 1
 
     if out ~= nil then
@@ -252,7 +252,7 @@ function log.dmesg_working(msg, tag, tag_color)
         local counter = 0
 
         local function update(sec_remaining)
-            local new_y = ts_coord.y - (logger.dmesg_scroll_count - initial_scroll)
+            local new_y = ts_coord.y - (_log.dmesg_scroll_count - initial_scroll)
             if new_y < 1 then return end
 
             local time = util.sprintf("%ds", sec_remaining)
@@ -280,11 +280,11 @@ function log.dmesg_working(msg, tag, tag_color)
 
             counter = counter + 1
 
-            out.setCursorPos(table.unpack(logger.dmesg_restore_coord))
+            out.setCursorPos(table.unpack(_log.dmesg_restore_coord))
         end
 
         local function done(ok)
-            local new_y = ts_coord.y - (logger.dmesg_scroll_count - initial_scroll)
+            local new_y = ts_coord.y - (_log.dmesg_scroll_count - initial_scroll)
             if new_y < 1 then return end
 
             out.setCursorPos(ts_coord.x1, new_y)
@@ -299,7 +299,7 @@ function log.dmesg_working(msg, tag, tag_color)
 
             out.setTextColor(initial_color)
 
-            out.setCursorPos(table.unpack(logger.dmesg_restore_coord))
+            out.setCursorPos(table.unpack(_log.dmesg_restore_coord))
         end
 
         return update, done
@@ -312,28 +312,28 @@ end
 ---@param msg any message
 ---@param trace? boolean include file trace
 function log.debug(msg, trace)
-    if logger.debug then
+    if _log.debug then
         if trace then
             local info = debug.getinfo(2)
 
             if info.name ~= nil then
-                _log{DBG_TAG, info.short_src, COLON, info.name, FUNC, info.currentline, ARROW, msg}
+                write_log{DBG_TAG, info.short_src, COLON, info.name, FUNC, info.currentline, ARROW, msg}
             else
-                _log{DBG_TAG, info.short_src, COLON, info.currentline, ARROW, msg}
+                write_log{DBG_TAG, info.short_src, COLON, info.currentline, ARROW, msg}
             end
         else
-            _log{DBG_TAG, msg}
+            write_log{DBG_TAG, msg}
         end
     end
 end
 
 -- log info messages
 ---@param msg any message
-function log.info(msg) _log{INF_TAG, msg} end
+function log.info(msg) write_log{INF_TAG, msg} end
 
 -- log warning messages
 ---@param msg any message
-function log.warning(msg) _log{WRN_TAG, msg} end
+function log.warning(msg) write_log{WRN_TAG, msg} end
 
 -- log error messages
 ---@param msg any message
@@ -343,17 +343,17 @@ function log.error(msg, trace)
         local info = debug.getinfo(2)
 
         if info.name ~= nil then
-            _log{ERR_TAG, info.short_src, COLON, info.name, FUNC, info.currentline, ARROW, msg}
+            write_log{ERR_TAG, info.short_src, COLON, info.name, FUNC, info.currentline, ARROW, msg}
         else
-            _log{ERR_TAG, info.short_src, COLON, info.currentline, ARROW, msg}
+            write_log{ERR_TAG, info.short_src, COLON, info.currentline, ARROW, msg}
         end
     else
-        _log{ERR_TAG, msg}
+        write_log{ERR_TAG, msg}
     end
 end
 
 -- log fatal errors
 ---@param msg any message
-function log.fatal(msg) _log{FTL_TAG, msg} end
+function log.fatal(msg) write_log{FTL_TAG, msg} end
 
 return log
diff --git a/scada-common/network.lua b/scada-common/network.lua
index 1891f5e..317d517 100644
--- a/scada-common/network.lua
+++ b/scada-common/network.lua
@@ -1,5 +1,5 @@
 --
--- Network Communications
+-- Network Communications and Message Authentication
 --
 
 local comms  = require("scada-common.comms")
@@ -18,7 +18,7 @@ local array  = require("lockbox.util.array")
 local network = {}
 
 -- cryptography engine
-local c_eng = {
+local _crypt = {
     key = nil,
     hmac = nil
 }
@@ -40,13 +40,13 @@ function network.init_mac(passkey)
     key_deriv.setPassword(passkey)
     key_deriv.finish()
 
-    c_eng.key = array.fromHex(key_deriv.asHex())
+    _crypt.key = array.fromHex(key_deriv.asHex())
 
     -- initialize HMAC
-    c_eng.hmac = hmac()
-    c_eng.hmac.setBlockSize(64)
-    c_eng.hmac.setDigest(md5)
-    c_eng.hmac.setKey(c_eng.key)
+    _crypt.hmac = hmac()
+    _crypt.hmac.setBlockSize(64)
+    _crypt.hmac.setDigest(md5)
+    _crypt.hmac.setKey(_crypt.key)
 
     local init_time = util.time_ms() - start
     log.info("NET: network.init_mac completed in " .. init_time .. "ms")
@@ -56,7 +56,7 @@ end
 
 -- de-initialize message authentication system
 function network.deinit_mac()
-    c_eng.key, c_eng.hmac = nil, nil
+    _crypt.key, _crypt.hmac = nil, nil
 end
 
 -- generate HMAC of message
@@ -65,11 +65,11 @@ end
 local function compute_hmac(message)
     -- local start = util.time_ms()
 
-    c_eng.hmac.init()
-    c_eng.hmac.update(stream.fromString(message))
-    c_eng.hmac.finish()
+    _crypt.hmac.init()
+    _crypt.hmac.update(stream.fromString(message))
+    _crypt.hmac.finish()
 
-    local hash = c_eng.hmac.asHex()
+    local hash = _crypt.hmac.asHex()
 
     -- log.debug("NET: compute_hmac(): hmac-md5 = " .. util.strval(hash) ..  " (took " .. (util.time_ms() - start) .. "ms)")
 
@@ -112,7 +112,7 @@ function network.nic(modem)
         self.iface     = ppm.get_iface(modem)
         self.name      = util.c(util.trinary(modem.isWireless(), "WLAN_PHY", "ETH_PHY"), "{", self.iface, "}")
         self.connected = true
-        self.use_hash  = c_eng.hmac and modem.isWireless()
+        self.use_hash  = _crypt.hmac and modem.isWireless()
 
         -- open only previously opened channels
         modem.closeAll()
diff --git a/scada-common/ppm.lua b/scada-common/ppm.lua
index ea310a3..faf74a6 100644
--- a/scada-common/ppm.lua
+++ b/scada-common/ppm.lua
@@ -22,7 +22,7 @@ ppm.VIRTUAL_DEVICE_TYPE   = VIRTUAL_DEVICE_TYPE
 
 local REPORT_FREQUENCY = 20 -- log every 20 faults per function
 
-local ppm_sys = {
+local _ppm = {
     mounts = {},    ---@type { [string]: ppm_entry }
     next_vid = 0,
     auto_cf = false,
@@ -66,7 +66,7 @@ local function peri_init(iface)
             if status then
                 -- auto fault clear
                 if self.auto_cf then self.faulted = false end
-                if ppm_sys.auto_cf then ppm_sys.faulted = false end
+                if _ppm.auto_cf then _ppm.faulted = false end
 
                 self.fault_counts[key] = 0
 
@@ -78,10 +78,10 @@ local function peri_init(iface)
                 self.faulted = true
                 self.last_fault = result
 
-                ppm_sys.faulted = true
-                ppm_sys.last_fault = result
+                _ppm.faulted = true
+                _ppm.last_fault = result
 
-                if not ppm_sys.mute and (self.fault_counts[key] % REPORT_FREQUENCY == 0) then
+                if not _ppm.mute and (self.fault_counts[key] % REPORT_FREQUENCY == 0) then
                     local count_str = ""
                     if self.fault_counts[key] > 0 then
                         count_str = " [" .. self.fault_counts[key] .. " total faults]"
@@ -92,7 +92,7 @@ local function peri_init(iface)
 
                 self.fault_counts[key] = self.fault_counts[key] + 1
 
-                if result == "Terminated" then ppm_sys.terminate = true end
+                if result == "Terminated" then _ppm.terminate = true end
 
                 return ACCESS_FAULT, result
             end
@@ -159,10 +159,10 @@ local function peri_init(iface)
                 self.faulted = true
                 self.last_fault = UNDEFINED_FIELD
 
-                ppm_sys.faulted = true
-                ppm_sys.last_fault = UNDEFINED_FIELD
+                _ppm.faulted = true
+                _ppm.last_fault = UNDEFINED_FIELD
 
-                if not ppm_sys.mute and (self.fault_counts[key] % REPORT_FREQUENCY == 0) then
+                if not _ppm.mute and (self.fault_counts[key] % REPORT_FREQUENCY == 0) then
                     local count_str = ""
                     if self.fault_counts[key] > 0 then
                         count_str = " [" .. self.fault_counts[key] .. " total calls]"
@@ -193,35 +193,35 @@ end
 -- REPORTING --
 
 -- silence error prints
-function ppm.disable_reporting() ppm_sys.mute = true end
+function ppm.disable_reporting() _ppm.mute = true end
 
 -- allow error prints
-function ppm.enable_reporting() ppm_sys.mute = false end
+function ppm.enable_reporting() _ppm.mute = false end
 
 -- FAULT MEMORY --
 
 -- enable automatically clearing fault flag
-function ppm.enable_afc() ppm_sys.auto_cf = true end
+function ppm.enable_afc() _ppm.auto_cf = true end
 
 -- disable automatically clearing fault flag
-function ppm.disable_afc() ppm_sys.auto_cf = false end
+function ppm.disable_afc() _ppm.auto_cf = false end
 
 -- clear fault flag
-function ppm.clear_fault() ppm_sys.faulted = false end
+function ppm.clear_fault() _ppm.faulted = false end
 
 -- check fault flag
 ---@nodiscard
-function ppm.is_faulted() return ppm_sys.faulted end
+function ppm.is_faulted() return _ppm.faulted end
 
 -- get the last fault message
 ---@nodiscard
-function ppm.get_last_fault() return ppm_sys.last_fault end
+function ppm.get_last_fault() return _ppm.last_fault end
 
 -- TERMINATION --
 
 -- if a caught error was a termination request
 ---@nodiscard
-function ppm.should_terminate() return ppm_sys.terminate end
+function ppm.should_terminate() return _ppm.terminate end
 
 -- MOUNTING --
 
@@ -229,12 +229,12 @@ function ppm.should_terminate() return ppm_sys.terminate end
 function ppm.mount_all()
     local ifaces = peripheral.getNames()
 
-    ppm_sys.mounts = {}
+    _ppm.mounts = {}
 
     for i = 1, #ifaces do
-        ppm_sys.mounts[ifaces[i]] = peri_init(ifaces[i])
+        _ppm.mounts[ifaces[i]] = peri_init(ifaces[i])
 
-        log.info(util.c("PPM: found a ", ppm_sys.mounts[ifaces[i]].type, " (", ifaces[i], ")"))
+        log.info(util.c("PPM: found a ", _ppm.mounts[ifaces[i]].type, " (", ifaces[i], ")"))
     end
 
     if #ifaces == 0 then
@@ -253,10 +253,10 @@ function ppm.mount(iface)
 
     for i = 1, #ifaces do
         if iface == ifaces[i] then
-            ppm_sys.mounts[iface] = peri_init(iface)
+            _ppm.mounts[iface] = peri_init(iface)
 
-            pm_type = ppm_sys.mounts[iface].type
-            pm_dev = ppm_sys.mounts[iface].dev
+            pm_type = _ppm.mounts[iface].type
+            pm_dev = _ppm.mounts[iface].dev
 
             log.info(util.c("PPM: mount(", iface, ") -> found a ", pm_type))
             break
@@ -278,12 +278,12 @@ function ppm.remount(iface)
     for i = 1, #ifaces do
         if iface == ifaces[i] then
             log.info(util.c("PPM: remount(", iface, ") -> is a ", pm_type))
-            ppm.unmount(ppm_sys.mounts[iface].dev)
+            ppm.unmount(_ppm.mounts[iface].dev)
 
-            ppm_sys.mounts[iface] = peri_init(iface)
+            _ppm.mounts[iface] = peri_init(iface)
 
-            pm_type = ppm_sys.mounts[iface].type
-            pm_dev = ppm_sys.mounts[iface].dev
+            pm_type = _ppm.mounts[iface].type
+            pm_dev = _ppm.mounts[iface].dev
 
             log.info(util.c("PPM: remount(", iface, ") -> remounted a ", pm_type))
             break
@@ -297,24 +297,24 @@ end
 ---@nodiscard
 ---@return string type, table device
 function ppm.mount_virtual()
-    local iface = "ppm_vdev_" .. ppm_sys.next_vid
+    local iface = "ppm_vdev_" .. _ppm.next_vid
 
-    ppm_sys.mounts[iface] = peri_init("__virtual__")
-    ppm_sys.next_vid = ppm_sys.next_vid + 1
+    _ppm.mounts[iface] = peri_init("__virtual__")
+    _ppm.next_vid = _ppm.next_vid + 1
 
     log.info(util.c("PPM: mount_virtual() -> allocated new virtual device ", iface))
 
-    return ppm_sys.mounts[iface].type, ppm_sys.mounts[iface].dev
+    return _ppm.mounts[iface].type, _ppm.mounts[iface].dev
 end
 
 -- manually unmount a peripheral from the PPM
 ---@param device table device table
 function ppm.unmount(device)
     if device then
-        for iface, data in pairs(ppm_sys.mounts) do
+        for iface, data in pairs(_ppm.mounts) do
             if data.dev == device then
                 log.warning(util.c("PPM: manually unmounted ", data.type, " mounted to ", iface))
-                ppm_sys.mounts[iface] = nil
+                _ppm.mounts[iface] = nil
                 break
             end
         end
@@ -330,7 +330,7 @@ function ppm.handle_unmount(iface)
     local pm_type = nil
 
     -- what got disconnected?
-    local lost_dev = ppm_sys.mounts[iface]
+    local lost_dev = _ppm.mounts[iface]
 
     if lost_dev then
         pm_type = lost_dev.type
@@ -341,18 +341,18 @@ function ppm.handle_unmount(iface)
         log.error(util.c("PPM: lost device unknown to the PPM mounted to ", iface))
     end
 
-    ppm_sys.mounts[iface] = nil
+    _ppm.mounts[iface] = nil
 
     return pm_type, pm_dev
 end
 
 -- log all mounts, to be used if `ppm.mount_all` is called before logging is ready
 function ppm.log_mounts()
-    for iface, mount in pairs(ppm_sys.mounts) do
+    for iface, mount in pairs(_ppm.mounts) do
         log.info(util.c("PPM: had found a ", mount.type, " (", iface, ")"))
     end
 
-    if util.table_len(ppm_sys.mounts) == 0 then
+    if util.table_len(_ppm.mounts) == 0 then
         log.warning("PPM: no devices had been found")
     end
 end
@@ -369,7 +369,7 @@ function ppm.list_avail() return peripheral.getNames() end
 ---@return { [string]: ppm_entry } mounts
 function ppm.list_mounts()
     local list = {}
-    for k, v in pairs(ppm_sys.mounts) do list[k] = v end
+    for k, v in pairs(_ppm.mounts) do list[k] = v end
     return list
 end
 
@@ -379,7 +379,7 @@ end
 ---@return string|nil iface CC peripheral interface
 function ppm.get_iface(device)
     if device then
-        for iface, data in pairs(ppm_sys.mounts) do
+        for iface, data in pairs(_ppm.mounts) do
             if data.dev == device then return iface end
         end
     end
@@ -392,8 +392,8 @@ end
 ---@param iface string CC peripheral interface
 ---@return { [string]: function }|nil device function table
 function ppm.get_periph(iface)
-    if ppm_sys.mounts[iface] then
-        return ppm_sys.mounts[iface].dev
+    if _ppm.mounts[iface] then
+        return _ppm.mounts[iface].dev
     else return nil end
 end
 
@@ -402,8 +402,8 @@ end
 ---@param iface string CC peripheral interface
 ---@return string|nil type
 function ppm.get_type(iface)
-    if ppm_sys.mounts[iface] then
-        return ppm_sys.mounts[iface].type
+    if _ppm.mounts[iface] then
+        return _ppm.mounts[iface].type
     else return nil end
 end
 
@@ -414,7 +414,7 @@ end
 function ppm.get_all_devices(name)
     local devices = {}
 
-    for _, data in pairs(ppm_sys.mounts) do
+    for _, data in pairs(_ppm.mounts) do
         if data.type == name then
             table.insert(devices, data.dev)
         end
@@ -430,7 +430,7 @@ end
 function ppm.get_device(name)
     local device = nil
 
-    for _, data in pairs(ppm_sys.mounts) do
+    for _, data in pairs(_ppm.mounts) do
         if data.type == name then
             device = data.dev
             break
@@ -455,7 +455,7 @@ function ppm.get_wireless_modem()
     local w_modem = nil
     local emulated_env = periphemu ~= nil
 
-    for _, device in pairs(ppm_sys.mounts) do
+    for _, device in pairs(_ppm.mounts) do
         if device.type == "modem" and (emulated_env or device.dev.isWireless()) then
             w_modem = device.dev
             break
@@ -471,7 +471,7 @@ end
 function ppm.get_monitor_list()
     local list = {}
 
-    for iface, device in pairs(ppm_sys.mounts) do
+    for iface, device in pairs(_ppm.mounts) do
         if device.type == "monitor" then list[iface] = device end
     end